Workflow Inputs¶

OpenStudio-HPXML requires a building description in an HPXML file format. HPXML is an open data standard for collecting and transferring home energy data. Using HPXML files reduces the complexity and effort for software developers to leverage the EnergyPlus simulation engine.

Using HPXML¶

HPXML is an flexible and extensible format, where nearly all elements in the schema are optional and custom elements can be included. Because of this, a stricter set of requirements for the HPXML file have been developed for purposes of running EnergyPlus simulations.

HPXML files submitted to OpenStudio-HPXML should undergo a two step validation process:

Validation against the HPXML Schema

The HPXML XSD Schema can be found at HPXMLtoOpenStudio/resources/HPXML.xsd. It should be used by the software developer to validate their HPXML file prior to running the simulation. XSD Schemas are used to validate what elements/attributes/enumerations are available, data types for elements/attributes, the number/order of children elements, etc.

OpenStudio-HPXML does not validate the HPXML file against the XSD Schema and assumes the file submitted is valid. However, OpenStudio-HPXML does automatically check for valid data types (e.g., integer vs string), enumeration choices, and numeric values within min/max.

Validation using Schematron

The Schematron document for the EnergyPlus use case can be found at HPXMLtoOpenStudio/resources/EPvalidator.xml. Schematron is a rule-based validation language, expressed in XML using XPath expressions, for validating the presence or absence of inputs in XML files. As opposed to an XSD Schema, a Schematron document validates constraints and requirements based on conditionals and other logical statements. For example, if an element is specified with a particular value, the applicable enumerations of another element may change.

OpenStudio-HPXML automatically validates the HPXML file against the Schematron document and reports any validation errors, but software developers may find it beneficial to also integrate Schematron validation into their software.

Important

Usage of both validation approaches (XSD and Schematron) is recommended for developers actively working on creating HPXML files for EnergyPlus simulations:

Validation against XSD for general correctness and usage of HPXML
Validation against Schematron for understanding XML document requirements specific to running EnergyPlus

Input Defaults¶

A large number of elements in the HPXML file are optional and can be defaulted. Default values, equations, and logic are described throughout this documentation.

For example, suppose a HPXML file has a refrigerator defined as follows:

<Refrigerator>
  <SystemIdentifier id='Refrigerator1'/>
</Refrigerator>

Default values would be used for the refrigerator energy use, location, and schedule:

<Refrigerator>
  <SystemIdentifier id='Refrigerator1'/>
  <Location dataSource='software'>living space</Location>
  <RatedAnnualkWh dataSource='software'>691.0</RatedAnnualkWh>
  <PrimaryIndicator dataSource='software'>true</PrimaryIndicator>
  <extension>
    <UsageMultiplier dataSource='software'>1.0</UsageMultiplier>
    <WeekdayScheduleFractions dataSource='software'>0.040, 0.039, 0.038, 0.037, 0.036, 0.036, 0.038, 0.040, 0.041, 0.041, 0.040, 0.040, 0.042, 0.042, 0.042, 0.041, 0.044, 0.048, 0.050, 0.048, 0.047, 0.046, 0.044, 0.041</WeekdayScheduleFractions>
    <WeekendScheduleFractions dataSource='software'>0.040, 0.039, 0.038, 0.037, 0.036, 0.036, 0.038, 0.040, 0.041, 0.041, 0.040, 0.040, 0.042, 0.042, 0.042, 0.041, 0.044, 0.048, 0.050, 0.048, 0.047, 0.046, 0.044, 0.041</WeekendScheduleFractions>
    <MonthlyScheduleMultipliers dataSource='software'>0.837, 0.835, 1.084, 1.084, 1.084, 1.096, 1.096, 1.096, 1.096, 0.931, 0.925, 0.837</MonthlyScheduleMultipliers>
  </extension>
</Refrigerator>

These defaults will be reflected in the EnergyPlus simulation results.

Note

The OpenStudio-HPXML workflow generally treats missing elements differently than missing values. For example, if there is no Refrigerator element defined, the model will proceed without refrigerator energy use. On the other hand, if there is a Refrigerator element but with no values defined (i.e., no Location or RatedAnnualkWh), it is assumed that a refrigerator exists but its properties are unknown, so they will be defaulted in the model.

See HPXML Defaults for information on how default values can be inspected.

HPXML Software Info¶

High-level simulation inputs are entered in /HPXML/SoftwareInfo.

HPXML Simulation Control¶

EnergyPlus simulation controls are entered in /HPXML/SoftwareInfo/extension/SimulationControl.

Element Type Units Constraints Required Default Description

Timestep integer minutes Divisor of 60 No 60 (1 hour) Timestep

BeginMonth integer 1 - 12 [1] No 1 (January) Run period start date

BeginDayOfMonth integer 1 - 31 No 1 Run period start date

EndMonth integer 1 - 12 No 12 (December) Run period end date

EndDayOfMonth integer 1 - 31 No Run period end date

CalendarYear integer > 1600 No 2007 (for TMY weather) [2] Calendar year (for start day of week)

DaylightSaving/Enabled boolean No true Daylight savings enabled?

[1] BeginMonth/BeginDayOfMonth date must occur before EndMonth/EndDayOfMonth date (e.g., a run period from 10/1 to 3/31 is invalid).

[2] CalendarYear only applies to TMY (Typical Meteorological Year) weather. For AMY (Actual Meteorological Year) weather, the AMY year will be used regardless of what is specified.

If daylight saving is enabled, additional information is specified in DaylightSaving.

Element Type Units Constraints Required Default Description

BeginMonth and BeginDayOfMonth integer 1 - 12 and 1 - 31 No EPW else 3/12 (March 12) [3] Start date

EndMonth and EndDayOfMonth integer 1 - 12 and 1 - 31 No EPW else 11/5 (November 5) End date

[3] Daylight savings dates will be defined according to the EPW weather file header; if not available, fallback default values listed above will be used.

HPXML HVAC Sizing Control¶

HVAC equipment sizing controls are entered in /HPXML/SoftwareInfo/extension/HVACSizingControl.

Element Type Units Constraints Required Default Description

AllowIncreasedFixedCapacities boolean No false Logic for fixed capacity HVAC equipment [4]

UseMaxLoadForHeatPumps boolean No true Logic for autosized heat pumps [5]

[4] If AllowIncreasedFixedCapacities is true, the larger of user-specified fixed capacity and design load will be used (to reduce potential for unmet loads); otherwise user-specified fixed capacity is used.

[5] If UseMaxLoadForHeatPumps is true, autosized heat pumps are sized based on the maximum of heating/cooling design loads; otherwise sized per ACCA Manual J/S based on cooling design loads with some oversizing allowances for heating design loads.

HPXML Schedules¶

Schedules for a variety of building features can be 1) specified via simple inputs, 2) specified via detailed inputs, or 3) defaulted.

Simple Schedule Inputs¶

Simple schedule inputs are available as weekday/weekend fractions and monthly multipliers. For example, see the WeekdayScheduleFractions, WeekendScheduleFractions, and MonthlyScheduleMultipliers inputs for HPXML Building Occupancy.

Detailed Schedule Inputs¶

Detailed schedule inputs allow schedule values for every hour or timestep of the simulation. They can be smooth schedules, or they can reflect real-world or stochastic occupancy. Note that if detailed schedule inputs are used, they must be used for all building features; you cannot use detailed schedules for some features and simple/default schedules for other features.

Detailed schedule inputs are provided via a CSV file that should be referenced in the HPXML file at /HPXML/SoftwareInfo/extension/SchedulesFilePath. Each column must be normalized to MAX=1; that is, the schedules only define when energy is used, not how much energy is used. The columns in the schedule CSV are:

Column Name Required Description Affected by Vacancy

occupants Yes Occupant heat gain schedule. Yes

lighting_interior Yes Interior lighting energy use schedule. Yes

lighting_exterior Yes Exterior lighting energy use schedule. Yes

lighting_garage Yes Garage lighting energy use schedule. Yes

lighting_exterior_holiday Yes Exterior holiday lighting energy use schedule. Yes

cooking_range Yes Cooking range & oven energy use schedule. Yes

refrigerator Yes Primary refrigerator energy use schedule. No

extra_refrigerator Yes Non-primary refrigerator energy use schedule. No

freezer Yes Freezer energy use schedule. No

dishwasher Yes Dishwasher energy use schedule. Yes

clothes_washer Yes Clothes washer energy use schedule. Yes

clothes_dryer Yes Clothes dryer energy use schedule. Yes

ceiling_fan Yes Ceiling fan energy use schedule. Yes

plug_loads_other Yes Other plug load energy use schedule. Yes

plug_loads_tv Yes Television plug load energy use schedule. Yes

plug_loads_vehicle Yes Electric vehicle plug load energy use schedule. Yes

plug_loads_well_pump Yes Well pump plug load energy use schedule. Yes

fuel_loads_grill Yes Grill fuel load energy use schedule. Yes

fuel_loads_lighting Yes Lighting fuel load energy use schedule. Yes

fuel_loads_fireplace Yes Fireplace fuel load energy use schedule. Yes

pool_pump Yes Pool pump energy use schedule. No

pool_heater Yes Pool heater energy use schedule. No

hot_tub_pump Yes Hot tub pump energy use schedule. No

hot_tub_heater Yes Hot tub heater energy use schedule. No

hot_water_dishwasher Yes Dishwasher hot water use schedule. Yes

hot_water_clothes_washer Yes Clothes washer hot water use schedule. Yes

hot_water_fixtures Yes Fixtures (sinks, showers, baths) hot water use schedule. Yes

vacancy No 1=Home is vacant. Automatically overrides other columns. N/A

A couple schedule CSV file examples are provided in the HPXMLtoOpenStudio/resources/schedule_files directory.

A detailed stochastic or smooth schedule CSV file can also be automatically generated for you; see the Usage Instructions for the commands.

Default Schedules¶

If neither simple nor detailed inputs are provided, then schedules are defaulted. Default schedules are typically smooth, averaged schedules. These default schedules are described elsewhere in the documentation (e.g., see HPXML Building Occupancy).

HPXML Building Summary¶

High-level building summary information is entered in /HPXML/Building/BuildingDetails/BuildingSummary.

HPXML Site¶

Building site information is entered in /HPXML/Building/BuildingDetails/BuildingSummary/Site.

Element Type Units Constraints Required Default Notes

SiteType string See [6] No suburban Terrain type for infiltration model

ShieldingofHome string See [7] No normal Presence of nearby buildings, trees, obstructions for infiltration model

extension/Neighbors element >= 0 No <none> Presence of neighboring buildings for solar shading

[6] SiteType choices are “rural”, “suburban”, or “urban”.

[7] ShieldingofHome choices are “normal”, “exposed”, or “well-shielded”.

For each neighboring building defined, additional information is entered in a extension/Neighbors/NeighborBuilding.

Element Type Units Constraints Required Default Notes

Azimuth or Orientation integer or string deg or direction 0 - 359 or See [8] Yes Direction of neighbors (clockwise from North)

Distance double ft > 0 Yes Distance of neighbor from the dwelling unit

Height double ft > 0 No See [9] Height of neighbor

[8] Orientation choices are “northeast”, “east”, “southeast”, “south”, “southwest”, “west”, “northwest”, or “north”

[9] If Height not provided, assumed to be same height as the dwelling unit.

HPXML Building Occupancy¶

Building occupancy is entered in /HPXML/Building/BuildingDetails/BuildingSummary/BuildingOccupancy.

Element Type Units Constraints Required Default Notes

NumberofResidents integer >= 0 No <number of bedrooms> Number of occupants

extension/WeekdayScheduleFractions array No See [10] 24 comma-separated weekday fractions

extension/WeekendScheduleFractions array No 24 comma-separated weekend fractions

extension/MonthlyScheduleMultipliers array No See [11] 12 comma-separated monthly multipliers

[10] If WeekdayScheduleFractions or WeekendScheduleFractions not provided (and Detailed Schedule Inputs not used), default values from Figures 25 of the 2010 BAHSP are used: “0.061, 0.061, 0.061, 0.061, 0.061, 0.061, 0.061, 0.053, 0.025, 0.015, 0.015, 0.015, 0.015, 0.015, 0.015, 0.015, 0.018, 0.033, 0.054, 0.054, 0.054, 0.061, 0.061, 0.061”.

[11] If MonthlyScheduleMultipliers not provided (and Detailed Schedule Inputs not used), default values are used: “1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0”.

Note

The above inputs are only used to define heat gain from occupants. Usages of plug loads, appliances, hot water, etc. are driven by number of bedrooms, not number of occupants.

HPXML Building Construction¶

Building construction is entered in /HPXML/Building/BuildingDetails/BuildingSummary/BuildingConstruction.

Element Type Units Constraints Required Default Notes

ResidentialFacilityType string See [12] Yes Type of dwelling unit

NumberofConditionedFloors double > 0 Yes Number of conditioned floors (including a conditioned basement; excluding a conditioned crawlspace)

NumberofConditionedFloorsAboveGrade double > 0, <= NumberofConditionedFloors Yes Number of conditioned floors above grade (including a walkout basement)

NumberofBedrooms integer > 0 Yes Number of bedrooms

NumberofBathrooms integer > 0 No See [13] Number of bathrooms

ConditionedFloorArea double ft2 > 0 Yes Floor area within conditioned space boundary (excluding conditioned crawlspace floor area)

ConditionedBuildingVolume or AverageCeilingHeight double ft3 or ft > 0 No See [14] Volume/ceiling height within conditioned space boundary (including a conditioned basement/crawlspace)

extension/HasFlueOrChimney boolean No See [15] Presence of flue or chimney for infiltration model

[12] ResidentialFacilityType choices are “single-family detached”, “single-family attached”, “apartment unit”, or “manufactured home”.

[13] If NumberofBathrooms not provided, calculated as NumberofBedrooms/2 + 0.5 based on the 2010 BAHSP.

[14] If neither ConditionedBuildingVolume nor AverageCeilingHeight provided, AverageCeilingHeight defaults to the lesser of 8.0 and InfiltrationVolume / ConditionedFloorArea. If needed, additional defaulting is performed using the following relationship: ConditionedBuildingVolume = ConditionedFloorArea * AverageCeilingHeight + ConditionedCrawlspaceVolume.

[15]
If HasFlueOrChimney not provided, assumed to be true if any of the following conditions are met:

heating system is non-electric Furnace, Boiler, WallFurnace, FloorFurnace, Stove, PortableHeater, or FixedHeater and AFUE/Percent is less than 0.89,

heating system is non-electric Fireplace, or

water heater is non-electric with energy factor (or equivalent calculated from uniform energy factor) less than 0.63.

HPXML Weather Station¶

Weather information is entered in /HPXML/Building/BuildingDetails/ClimateandRiskZones/WeatherStation.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

Name string Yes Name of weather station

extension/EPWFilePath string Yes Path to the EnergyPlus weather file (EPW) [16]

[16] A full set of U.S. TMY3 weather files can be downloaded here.

HPXML Enclosure¶

The dwelling unit’s enclosure is entered in /HPXML/Building/BuildingDetails/Enclosure.

All surfaces that bound different space types of the dwelling unit (i.e., not just thermal boundary surfaces) must be specified in the HPXML file. For example, an attached garage would generally be defined by walls adjacent to conditioned space, walls adjacent to outdoors, a slab, and a roof or ceiling. For software tools that do not collect sufficient inputs for every required surface, the software developers will need to make assumptions about these surfaces or collect additional input.

Interior partition surfaces (e.g., walls between rooms inside conditioned space, or the floor between two conditioned stories) can be excluded.

For single-family attached (SFA) or multifamily (MF) buildings, surfaces between unconditioned space and the neighboring unit’s same unconditioned space should set InteriorAdjacentTo and ExteriorAdjacentTo to the same value. For example, a foundation wall between the unit’s vented crawlspace and the neighboring unit’s vented crawlspace would use InteriorAdjacentTo="crawlspace - vented" and ExteriorAdjacentTo="crawlspace - vented".

Warning

It is the software tool’s responsibility to provide the appropriate building surfaces. While some error-checking is in place, it is not possible to know whether some surfaces are incorrectly missing.

Also note that wall and roof surfaces do not require an azimuth/orientation to be specified. Rather, only the windows/skylights themselves require an azimuth/orientation. Thus, software tools can choose to use a single wall (or roof) surface to represent multiple wall (or roof) surfaces for the entire building if all their other properties (construction type, interior/exterior adjacency, etc.) are identical.

HPXML Air Infiltration¶

Building air leakage is entered in /HPXML/Building/BuildingDetails/Enclosure/AirInfiltration/AirInfiltrationMeasurement.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

BuildingAirLeakage/UnitofMeasure string See [17] Yes Units for air leakage

HousePressure double Pa > 0 See [18] House pressure with respect to outside [19]

BuildingAirLeakage/AirLeakage double > 0 Yes Value for air leakage

InfiltrationVolume double ft3 > 0, >= ConditionedBuildingVolume No ConditionedBuildingVolume Volume associated with infiltration measurement

[17] UnitofMeasure choices are “ACH” (air changes per hour at user-specified pressure), “CFM” (cubic feet per minute at user-specified pressure), or “ACHnatural” (natural air changes per hour).

[18] HousePressure only required if BuildingAirLeakage/UnitofMeasure is not “ACHnatural”.

[19] HousePressure typical value is 50 Pa.

HPXML Attics¶

If the dwelling unit has a vented attic, attic ventilation information can be optionally entered in /HPXML/Building/BuildingDetails/Enclosure/Attics/Attic[AtticType/Attic[Vented="true"]]/VentilationRate.

Element Type Units Constraints Required Default Notes

UnitofMeasure string See [20] No SLA Units for ventilation rate

Value double > 0 No 1/300 [21] Value for ventilation rate

[20] UnitofMeasure choices are “SLA” (specific leakage area) or “ACHnatural” (natural air changes per hour).

[21] Value default based on ANSI/RESNET/ICC 301-2019.

HPXML Foundations¶

If the dwelling unit has a vented crawlspace, crawlspace ventilation information can be optionally entered in /HPXML/Building/BuildingDetails/Enclosure/Foundations/Foundation[FoundationType/Crawlspace[Vented="true"]]/VentilationRate.

Element Type Units Constraints Required Default Notes

UnitofMeasure string See [22] No SLA Units for ventilation rate

Value double > 0 No 1/150 [23] Value for ventilation rate

[22] UnitofMeasure only choice is “SLA” (specific leakage area).

[23] Value default based on ANSI/RESNET/ICC 301-2019.

HPXML Roofs¶

Each pitched or flat roof surface that is exposed to ambient conditions is entered as an /HPXML/Building/BuildingDetails/Enclosure/Roofs/Roof.

For a multifamily building where the dwelling unit has another dwelling unit above it, the surface between the two dwelling units should be considered a FrameFloor and not a Roof.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

InteriorAdjacentTo string See [24] Yes Interior adjacent space type

Area double ft2 > 0 Yes Gross area (including skylights)

Azimuth or Orientation integer or string deg or direction 0 - 359 or See [25] No See [26] Direction (clockwise from North)

RoofType string See [27] No asphalt or fiberglass shingles Roof type

RoofColor or SolarAbsorptance string or double See [28] or 0 - 1 No medium Roof color or solar absorptance [29]

Emittance double 0 - 1 No 0.90 Emittance

InteriorFinish/Type string See [30] No See [31] Interior finish material

InteriorFinish/Thickness double in >= 0 No 0.5 Interior finish thickness

Pitch integer ?:12 >= 0 Yes Pitch

RadiantBarrier boolean No false Presence of radiant barrier

RadiantBarrierGrade integer 1 - 3 No 1 Radiant barrier installation grade

Insulation/SystemIdentifier id Yes Unique identifier

Insulation/AssemblyEffectiveRValue double F-ft2-hr/Btu > 0 Yes Assembly R-value [32]

[24] InteriorAdjacentTo choices are “attic - vented”, “attic - unvented”, “living space”, or “garage”. See HPXML Locations for descriptions.

[25] Orientation choices are “northeast”, “east”, “southeast”, “south”, “southwest”, “west”, “northwest”, or “north”

[26] If neither Azimuth nor Orientation provided, modeled as four surfaces of equal area facing every direction.

[27] RoofType choices are “asphalt or fiberglass shingles”, “wood shingles or shakes”, “shingles”, “slate or tile shingles”, “metal surfacing”, “plastic/rubber/synthetic sheeting”, “expanded polystyrene sheathing”, “concrete”, or “cool roof”.

[28] RoofColor choices are “light”, “medium”, “medium dark”, “dark”, or “reflective”.

[29]
If SolarAbsorptance not provided, defaults based on RoofType and RoofColor:

asphalt or fiberglass shingles: dark=0.92, medium dark=0.89, medium=0.85, light=0.75, reflective=0.50

wood shingles or shakes: dark=0.92, medium dark=0.89, medium=0.85, light=0.75, reflective=0.50

shingles: dark=0.92, medium dark=0.89, medium=0.85, light=0.75, reflective=0.50

slate or tile shingles: dark=0.90, medium dark=0.83, medium=0.75, light=0.60, reflective=0.30

metal surfacing: dark=0.90, medium dark=0.83, medium=0.75, light=0.60, reflective=0.30

plastic/rubber/synthetic sheeting: dark=0.90, medium dark=0.83, medium=0.75, light=0.60, reflective=0.30

expanded polystyrene sheathing: dark=0.92, medium dark=0.89, medium=0.85, light=0.75, reflective=0.50

concrete: dark=0.90, medium dark=0.83, medium=0.75, light=0.65, reflective=0.50

cool roof: 0.30

[30] InteriorFinish/Type choices are “gypsum board”, “gypsum composite board”, “plaster”, “wood”, “other”, or “none”.

[31] InteriorFinish/Type defaults to “gypsum board” if InteriorAdjacentTo is living space, otherwise “none”.

[32] AssemblyEffectiveRValue includes all material layers, interior/exterior air films, and insulation installation grade.

HPXML Rim Joists¶

Each rim joist surface (i.e., the perimeter of floor joists typically found between stories of a building or on top of a foundation wall) is entered as an /HPXML/Building/BuildingDetails/Enclosure/RimJoists/RimJoist.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

ExteriorAdjacentTo string See [33] Yes Exterior adjacent space type

InteriorAdjacentTo string See [34] Yes Interior adjacent space type

Area double ft2 > 0 Yes Gross area

Azimuth or Orientation integer or string deg or direction 0 - 359 or See [35] No See [36] Direction (clockwise from North)

Siding string See [37] No wood siding Siding material

Color or SolarAbsorptance string or double See [38] or 0 - 1 No medium Color or solar absorptance [39]

Emittance double 0 - 1 No 0.90 Emittance

Insulation/SystemIdentifier id Yes Unique identifier

Insulation/AssemblyEffectiveRValue double F-ft2-hr/Btu > 0 Yes Assembly R-value [40]

[33] ExteriorAdjacentTo choices are “outside”, “attic - vented”, “attic - unvented”, “basement - conditioned”, “basement - unconditioned”, “crawlspace - vented”, “crawlspace - unvented”, “crawlspace - conditioned”, “garage”, “other housing unit”, “other heated space”, “other multifamily buffer space”, or “other non-freezing space”. See HPXML Locations for descriptions.

[34] InteriorAdjacentTo choices are “living space”, “attic - vented”, “attic - unvented”, “basement - conditioned”, “basement - unconditioned”, “crawlspace - vented”, “crawlspace - unvented”, “crawlspace - conditioned”, or “garage”. See HPXML Locations for descriptions.

[35] Orientation choices are “northeast”, “east”, “southeast”, “south”, “southwest”, “west”, “northwest”, or “north”

[36] If neither Azimuth nor Orientation provided, modeled as four surfaces of equal area facing every direction.

[37] Siding choices are “wood siding”, “vinyl siding”, “stucco”, “fiber cement siding”, “brick veneer”, “aluminum siding”, “masonite siding”, “composite shingle siding”, “asbestos siding”, “synthetic stucco”, or “none”.

[38] Color choices are “light”, “medium”, “medium dark”, “dark”, or “reflective”.

[39]
If SolarAbsorptance not provided, defaults based on Color:

dark: 0.95

medium dark: 0.85

medium: 0.70

light: 0.50

reflective: 0.30

[40] AssemblyEffectiveRValue includes all material layers, interior/exterior air films, and insulation installation grade.

HPXML Walls¶

Each wall that has no contact with the ground and bounds a space type is entered as an /HPXML/Building/BuildingDetails/Enclosure/Walls/Wall.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

ExteriorAdjacentTo string See [41] Yes Exterior adjacent space type

InteriorAdjacentTo string See [42] Yes Interior adjacent space type

WallType element 1 [43] Yes Wall type (for thermal mass)

Area double ft2 > 0 Yes Gross area (including doors/windows)

Azimuth or Orientation integer or string deg or direction 0 - 359 or See [44] No See [45] Direction (clockwise from North)

Siding string See [46] No wood siding Siding material

Color or SolarAbsorptance string or double See [47] or 0 - 1 No medium Color or solar absorptance [48]

Emittance double 0 - 1 No 0.90 Emittance

InteriorFinish/Type string See [49] No See [50] Interior finish material

InteriorFinish/Thickness double in >= 0 No 0.5 Interior finish thickness

Insulation/SystemIdentifier id Yes Unique identifier

Insulation/AssemblyEffectiveRValue double F-ft2-hr/Btu > 0 Yes Assembly R-value [51]

[41] ExteriorAdjacentTo choices are “outside”, “attic - vented”, “attic - unvented”, “basement - conditioned”, “basement - unconditioned”, “crawlspace - vented”, “crawlspace - unvented”, “crawlspace - conditioned”, “garage”, “other housing unit”, “other heated space”, “other multifamily buffer space”, or “other non-freezing space”. See HPXML Locations for descriptions.

[42] InteriorAdjacentTo choices are “living space”, “attic - vented”, “attic - unvented”, “basement - conditioned”, “basement - unconditioned”, “crawlspace - vented”, “crawlspace - unvented”, “crawlspace - conditioned”, or “garage”. See HPXML Locations for descriptions.

[43] WallType child element choices are WoodStud, DoubleWoodStud, ConcreteMasonryUnit, StructurallyInsulatedPanel, InsulatedConcreteForms, SteelFrame, SolidConcrete, StructuralBrick, StrawBale, Stone, LogWall, or Adobe.

[44] Orientation choices are “northeast”, “east”, “southeast”, “south”, “southwest”, “west”, “northwest”, or “north”

[45] If neither Azimuth nor Orientation provided, modeled as four surfaces of equal area facing every direction.

[46] Siding choices are “wood siding”, “vinyl siding”, “stucco”, “fiber cement siding”, “brick veneer”, “aluminum siding”, “masonite siding”, “composite shingle siding”, “asbestos siding”, “synthetic stucco”, or “none”.

[47] Color choices are “light”, “medium”, “medium dark”, “dark”, or “reflective”.

[48]
If SolarAbsorptance not provided, defaults based on Color:

dark: 0.95

medium dark: 0.85

medium: 0.70

light: 0.50

reflective: 0.30

[49] InteriorFinish/Type choices are “gypsum board”, “gypsum composite board”, “plaster”, “wood”, “other”, or “none”.

[50] InteriorFinish/Type defaults to “gypsum board” if InteriorAdjacentTo is living space or basement - conditioned, otherwise “none”.

[51] AssemblyEffectiveRValue includes all material layers, interior/exterior air films, and insulation installation grade.

HPXML Foundation Walls¶

Each wall that is in contact with the ground should be specified as an /HPXML/Building/BuildingDetails/Enclosure/FoundationWalls/FoundationWall.

Other walls (e.g., wood framed walls) that are connected to a below-grade space but have no contact with the ground should be specified as a Wall and not a FoundationWall.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

ExteriorAdjacentTo string See [52] Yes Exterior adjacent space type [53]

InteriorAdjacentTo string See [54] Yes Interior adjacent space type

Type string See [55] No solid concrete Type of material

Height double ft > 0 Yes Total height

Area or Length double ft2 or ft > 0 Yes Gross area (including doors/windows) or length

Azimuth or Orientation integer or string deg or direction 0 - 359 or See [56] No See [57] Direction (clockwise from North)

Thickness double inches > 0 No 8.0 Thickness excluding interior framing

DepthBelowGrade double ft 0 - Height Yes Depth below grade [58]

InteriorFinish/Type string See [59] No See [60] Interior finish material

InteriorFinish/Thickness double in >= 0 No 0.5 Interior finish thickness

Insulation/SystemIdentifier id Yes Unique identifier

Insulation/Layer[InstallationType="continuous - interior"] element 0 - 1 See [61] Interior insulation layer

Insulation/Layer[InstallationType="continuous - exterior"] element 0 - 1 See [62] Exterior insulation layer

Insulation/AssemblyEffectiveRValue double F-ft2-hr/Btu > 0 See [63] Assembly R-value [64]

[52] ExteriorAdjacentTo choices are “ground”, “basement - conditioned”, “basement - unconditioned”, “crawlspace - vented”, “crawlspace - unvented”, “crawlspace - conditioned”, “garage”, “other housing unit”, “other heated space”, “other multifamily buffer space”, or “other non-freezing space”. See HPXML Locations for descriptions.

[53] InteriorAdjacentTo choices are “basement - conditioned”, “basement - unconditioned”, “crawlspace - vented”, “crawlspace - unvented”, “crawlspace - conditioned”, or “garage”. See HPXML Locations for descriptions.

[54] Interior foundation walls (e.g., between basement and crawlspace) should not use “ground” even if the foundation wall has some contact with the ground due to the difference in below-grade depths of the two adjacent spaces.

[55] Type choices are “solid concrete”, “concrete block”, “concrete block foam core”, “concrete block vermiculite core”, “concrete block perlite core”, “concrete block solid core”, “double brick”, or “wood”.

[56] Orientation choices are “northeast”, “east”, “southeast”, “south”, “southwest”, “west”, “northwest”, or “north”

[57] If neither Azimuth nor Orientation provided, modeled as four surfaces of equal area facing every direction.

[58] For exterior foundation walls, depth below grade is relative to the ground plane. For interior foundation walls, depth below grade is the vertical span of foundation wall in contact with the ground. For example, an interior foundation wall between an 8 ft conditioned basement and a 3 ft crawlspace has a height of 8 ft and a depth below grade of 5 ft. Alternatively, an interior foundation wall between an 8 ft conditioned basement and an 8 ft unconditioned basement has a height of 8 ft and a depth below grade of 0 ft.

[59] InteriorFinish/Type choices are “gypsum board”, “gypsum composite board”, “plaster”, “wood”, “other”, or “none”.

[60] InteriorFinish/Type defaults to “gypsum board” if InteriorAdjacentTo is basement - conditioned, otherwise “none”.

[61] Layer[InstallationType=”continuous - interior”] only required if AssemblyEffectiveRValue is not provided.

[62] Layer[InstallationType=”continuous - exterior”] only required if AssemblyEffectiveRValue is not provided.

[63] AssemblyEffectiveRValue only required if Layer elements are not provided.

[64] AssemblyEffectiveRValue includes all material layers, interior air film, and insulation installation grade. R-value should not include exterior air film (for any above-grade exposure) or any soil thermal resistance.

If insulation layers are provided, additional information is entered in each FoundationWall/Insulation/Layer.

Element Type Units Constraints Required Default Notes

NominalRValue double F-ft2-hr/Btu >= 0 Yes R-value of the foundation wall insulation; use zero if no insulation

DistanceToTopOfInsulation double ft >= 0 No 0 Vertical distance from top of foundation wall to top of insulation

DistanceToBottomOfInsulation double ft See [65] No Height Vertical distance from top of foundation wall to bottom of insulation

[65] When NominalRValue is non-zero, DistanceToBottomOfInsulation must be greater than DistanceToTopOfInsulation and less than or equal to FoundationWall/Height.

HPXML Frame Floors¶

Each floor/ceiling surface that is not in contact with the ground (Slab) nor adjacent to ambient conditions above (Roof) is entered as an /HPXML/Building/BuildingDetails/Enclosure/FrameFloors/FrameFloor.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

ExteriorAdjacentTo string See [66] Yes Exterior adjacent space type

InteriorAdjacentTo string See [67] Yes Interior adjacent space type

Area double ft2 > 0 Yes Gross area

InteriorFinish/Type string See [68] No See [69] Interior finish material

InteriorFinish/Thickness double in >= 0 No 0.5 Interior finish thickness

Insulation/SystemIdentifier id Yes Unique identifier

Insulation/AssemblyEffectiveRValue double F-ft2-hr/Btu > 0 Yes Assembly R-value [70]

[66] ExteriorAdjacentTo choices are “outside”, “attic - vented”, “attic - unvented”, “basement - conditioned”, “basement - unconditioned”, “crawlspace - vented”, “crawlspace - unvented”, “crawlspace - conditioned”, “garage”, “other housing unit”, “other heated space”, “other multifamily buffer space”, or “other non-freezing space”. See HPXML Locations for descriptions.

[67] InteriorAdjacentTo choices are “living space”, “attic - vented”, “attic - unvented”, “basement - conditioned”, “basement - unconditioned”, “crawlspace - vented”, “crawlspace - unvented”, “crawlspace - conditioned”, or “garage”. See HPXML Locations for descriptions.

[68] InteriorFinish/Type choices are “gypsum board”, “gypsum composite board”, “plaster”, “wood”, “other”, or “none”.

[69] InteriorFinish/Type defaults to “gypsum board” if InteriorAdjacentTo is living space and the surface is a ceiling, otherwise “none”.

[70] AssemblyEffectiveRValue includes all material layers, interior/exterior air films, and insulation installation grade.

For frame floors adjacent to “other housing unit”, “other heated space”, “other multifamily buffer space”, or “other non-freezing space”, additional information is entered in FrameFloor.

Element Type Units Constraints Required Default Notes

extension/OtherSpaceAboveOrBelow string See [71] Yes Specifies if above/below the MF space type

[71] OtherSpaceAboveOrBelow choices are “above” or “below”.

HPXML Slabs¶

Each space type that borders the ground (i.e., basements, crawlspaces, garages, and slab-on-grade foundations) should have a slab entered as an /HPXML/Building/BuildingDetails/Enclosure/Slabs/Slab.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

InteriorAdjacentTo string See [72] Yes Interior adjacent space type

Area double ft2 > 0 Yes Gross area

Thickness double inches >= 0 No See [73] Thickness [74]

ExposedPerimeter double ft >= 0 Yes Perimeter exposed to ambient conditions [75]

DepthBelowGrade double ft >= 0 See [76] Depth from the top of the slab surface to grade

PerimeterInsulation/SystemIdentifier id Yes Unique identifier

PerimeterInsulation/Layer/NominalRValue double F-ft2-hr/Btu >= 0 Yes R-value of vertical insulation

PerimeterInsulation/Layer/InsulationDepth double ft >= 0 Yes Depth from grade to bottom of vertical insulation

UnderSlabInsulation/SystemIdentifier id Yes Unique identifier

UnderSlabInsulation/Layer/NominalRValue double F-ft2-hr/Btu >= 0 Yes R-value of horizontal insulation

UnderSlabInsulation/Layer/InsulationWidth double ft >= 0 See [77] Width from slab edge inward of horizontal insulation

UnderSlabInsulation/Layer/InsulationSpansEntireSlab boolean See [78] Whether horizontal insulation spans entire slab

extension/CarpetFraction double frac 0 - 1 No See [79] Fraction of slab covered by carpet

extension/CarpetRValue double F-ft2-hr/Btu >= 0 No See [80] Carpet R-value

[72] InteriorAdjacentTo choices are “living space”, “basement - conditioned”, “basement - unconditioned”, “crawlspace - vented”, “crawlspace - unvented”, “crawlspace - conditioned”, or “garage”. See HPXML Locations for descriptions.

[73] If Thickness not provided, defaults to 0 when adjacent to crawlspace and 4 inches for all other cases.

[74] For a crawlspace with a dirt floor, enter a thickness of zero.

[75] ExposedPerimeter includes any slab length that falls along the perimeter of the building’s footprint (i.e., is exposed to ambient conditions). So a basement slab edge adjacent to a garage or crawlspace, for example, should not be included.

[76] DepthBelowGrade only required if the attached foundation has no FoundationWalls. For foundation types with walls, the the slab’s position relative to grade is determined by the FoundationWall/DepthBelowGrade value.

[77] InsulationWidth only required if InsulationSpansEntireSlab=true is not provided.

[78] InsulationSpansEntireSlab=true only required if InsulationWidth is not provided.

[79] If CarpetFraction not provided, defaults to 0.8 when adjacent to conditioned space, otherwise 0.0.

[80] If CarpetRValue not provided, defaults to 2.0 when adjacent to conditioned space, otherwise 0.0.

HPXML Windows¶

Each window or glass door area is entered as an /HPXML/Building/BuildingDetails/Enclosure/Windows/Window.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

Area double ft2 > 0 Yes Total area

Azimuth or Orientation integer or string deg or direction 0 - 359 or See [81] Yes Direction (clockwise from North)

UFactor and/or GlassLayers double or string Btu/F-ft2-hr > 0 or See [82] Yes Full-assembly NFRC U-factor (including any storm window) or glass layers description

SHGC and/or GlassLayers double or string 0 - 1 Yes Full-assembly NFRC solar heat gain coefficient (including any storm window) or glass layers description

ExteriorShading/SummerShadingCoefficient double frac 0 - 1 No 1.00 Exterior summer shading coefficient (1=transparent, 0=opaque)

ExteriorShading/WinterShadingCoefficient double frac 0 - 1 No 1.00 Exterior winter shading coefficient (1=transparent, 0=opaque)

InteriorShading/SummerShadingCoefficient double frac 0 - 1 No 0.70 [83] Interior summer shading coefficient (1=transparent, 0=opaque)

InteriorShading/WinterShadingCoefficient double frac 0 - 1 No 0.85 [84] Interior winter shading coefficient (1=transparent, 0=opaque)

Overhangs element 0 - 1 No <none> Presence of overhangs (including roof eaves)

FractionOperable double frac 0 - 1 No 0.67 Operable fraction [85]

AttachedToWall idref See [86] Yes ID of attached wall

[81] Orientation choices are “northeast”, “east”, “southeast”, “south”, “southwest”, “west”, “northwest”, or “north”.

[82] GlassLayers choices are “single-pane”, “double-pane”, “triple-pane”, or “glass block”.

[83] InteriorShading/SummerShadingCoefficient default value indicates 30% reduction in solar heat gain, based on ANSI/RESNET/ICC 301-2019.

[84] InteriorShading/WinterShadingCoefficient default value indicates 15% reduction in solar heat gain, based on ANSI/RESNET/ICC 301-2019.

[85] FractionOperable reflects whether the windows are operable (can be opened), not how they are used by the occupants. If a Window represents a single window, the value should be 0 or 1. If a Window represents multiple windows (e.g., 4), the value should be between 0 and 1 (e.g., 0, 0.25, 0.5, 0.75, or 1). The total open window area for natural ventilation is calculated using A) the operable fraction, B) the assumption that 50% of the area of operable windows can be open, and C) the assumption that 20% of that openable area is actually opened by occupants whenever outdoor conditions are favorable for cooling.

[86] AttachedToWall must reference a Wall or FoundationWall.

If UFactor and SHGC are not provided and GlassLayers is not “glass block”, additional information is entered in Window.

Element Type Units Constraints Required Default Notes

FrameType element See [87] Yes Type of frame

FrameType/*/ThermalBreak boolean See [88] No false Whether the Aluminum or Metal frame has a thermal break

GlassType string See [89] No <none> Type of glass

GasFill string See [90] No See [91] Type of gas inside double/triple-pane windows

[87] FrameType child element choices are Aluminum, Fiberglass, Metal, Vinyl, or Wood.

[88] ThermalBreak is only valid if FrameType is Aluminum or Metal.

[89] GlassType choices are “clear”, “low-e”, “tinted”, “tinted/reflective”, or “reflective”. Do not specify this element if the window has clear glass.

[90] GasFill choices are “air”, “argon”, “krypton”, “xenon”, “nitrogen”, or “other”.

[91] If GasFill not provided, defaults to “air” for double-pane windows and “argon” for triple-pane windows.

If UFactor and SHGC are not provided, they are defaulted as follows:

GlassLayers FrameType ThermalBreak GlassType GasFill UFactor SHGC

single-pane Aluminum, Metal false clear – 1.27 0.75

single-pane Fiberglass, Vinyl, Wood – clear – 0.89 0.64

single-pane Aluminum, Metal false tinted, tinted/reflective – 1.27 0.64

single-pane Fiberglass, Vinyl, Wood – tinted, tinted/reflective – 0.89 0.54

double-pane Aluminum, Metal false clear air 0.81 0.67

double-pane Aluminum, Metal true clear air 0.60 0.67

double-pane Fiberglass, Vinyl, Wood – clear air 0.51 0.56

double-pane Aluminum, Metal false tinted, tinted/reflective air 0.81 0.55

double-pane Aluminum, Metal true tinted, tinted/reflective air 0.60 0.55

double-pane Fiberglass, Vinyl, Wood – tinted, tinted/reflective air 0.51 0.46

double-pane Fiberglass, Vinyl, Wood – low-e air 0.42 0.52

double-pane Aluminum, Metal true low-e <any but air> 0.47 0.62

double-pane Fiberglass, Vinyl, Wood – low-e <any but air> 0.39 0.52

double-pane Aluminum, Metal false reflective air 0.67 0.37

double-pane Aluminum, Metal true reflective air 0.47 0.37

double-pane Fiberglass, Vinyl, Wood – reflective air 0.39 0.31

double-pane Fiberglass, Vinyl, Wood – reflective <any but air> 0.36 0.31

triple-pane Fiberglass, Vinyl, Wood – low-e <any but air> 0.27 0.31

glass block – – – – 0.60 0.60

Warning

OpenStudio-HPXML will return an error if the combination of window properties is not in the above table.

If overhangs are specified, additional information is entered in Overhangs.

Element Type Units Constraints Required Default Notes

Depth double inches >= 0 Yes Depth of overhang

DistanceToTopOfWindow double ft >= 0 Yes Vertical distance from overhang to top of window

DistanceToBottomOfWindow double ft See [92] Yes Vertical distance from overhang to bottom of window [93]

[92] The difference between DistanceToBottomOfWindow and DistanceToTopOfWindow defines the height of the window.

[93] When Depth is non-zero, DistanceToBottomOfWindow must be greater than DistanceToTopOfWindow.

HPXML Skylights¶

Each skylight is entered as an /HPXML/Building/BuildingDetails/Enclosure/Skylights/Skylight.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

Area double ft2 > 0 Yes Total area

Azimuth or Orientation integer or string deg or direction 0 - 359 or See [94] Yes Direction (clockwise from North)

UFactor and/or GlassLayers double or string Btu/F-ft2-hr > 0 or See [95] Yes Full-assembly NFRC U-factor or glass layers description

SHGC and/or GlassLayers double or string 0 - 1 Yes Full-assembly NFRC solar heat gain coefficient or glass layers description

ExteriorShading/SummerShadingCoefficient double frac 0 - 1 No 1.00 Exterior summer shading coefficient (1=transparent, 0=opaque)

ExteriorShading/WinterShadingCoefficient double frac 0 - 1 No 1.00 Exterior winter shading coefficient (1=transparent, 0=opaque)

InteriorShading/SummerShadingCoefficient double frac 0 - 1 No 1.00 Interior summer shading coefficient (1=transparent, 0=opaque)

InteriorShading/WinterShadingCoefficient double frac 0 - 1 No 1.00 Interior winter shading coefficient (1=transparent, 0=opaque)

AttachedToRoof idref See [96] Yes ID of attached roof

[94] Orientation choices are “northeast”, “east”, “southeast”, “south”, “southwest”, “west”, “northwest”, or “north”

[95] GlassLayers choices are “single-pane”, “double-pane”, or “triple-pane”.

[96] AttachedToRoof must reference a Roof.

If UFactor and SHGC are not provided and GlassLayers is not “glass block”, additional information is entered in Skylight.

Element Type Units Constraints Required Default Notes

FrameType element See [97] Yes Type of frame

FrameType/*/ThermalBreak boolean See [98] No false Whether the Aluminum or Metal frame has a thermal break

GlassType string See [99] No <none> Type of glass

GasFill string See [100] No See [101] Type of gas inside double/triple-pane skylights

[97] FrameType child element choices are Aluminum, Fiberglass, Metal, Vinyl, or Wood.

[98] ThermalBreak is only valid if FrameType is Aluminum or Metal.

[99] GlassType choices are “clear”, “low-e”, “tinted”, “tinted/reflective”, or “reflective”. Do not specify this element if the skylight has clear glass.

[100] GasFill choices are “air”, “argon”, “krypton”, “xenon”, “nitrogen”, or “other”.

[101] If GasFill not provided, defaults to “air” for double-pane skylights and “argon” for triple-pane skylights.

If UFactor and SHGC are not provided, they are defaulted as follows:

GlassLayers FrameType ThermalBreak GlassType GasFill UFactor SHGC

single-pane Aluminum, Metal false clear – 1.98 0.75

single-pane Fiberglass, Vinyl, Wood – clear – 1.47 0.64

single-pane Aluminum, Metal false tinted, tinted/reflective – 1.98 0.64

single-pane Fiberglass, Vinyl, Wood – tinted, tinted/reflective – 1.47 0.54

double-pane Aluminum, Metal false clear air 1.30 0.67

double-pane Aluminum, Metal true clear air 1.10 0.67

double-pane Fiberglass, Vinyl, Wood – clear air 0.84 0.56

double-pane Aluminum, Metal false tinted, tinted/reflective air 1.30 0.55

double-pane Aluminum, Metal true tinted, tinted/reflective air 1.10 0.55

double-pane Fiberglass, Vinyl, Wood – tinted, tinted/reflective air 0.84 0.46

double-pane Fiberglass, Vinyl, Wood – low-e air 0.74 0.52

double-pane Aluminum, Metal true low-e <any but air> 0.95 0.62

double-pane Fiberglass, Vinyl, Wood – low-e <any but air> 0.68 0.52

double-pane Aluminum, Metal false reflective air 1.17 0.37

double-pane Aluminum, Metal true reflective air 0.98 0.37

double-pane Fiberglass, Vinyl, Wood – reflective air 0.71 0.31

double-pane Fiberglass, Vinyl, Wood – reflective <any but air> 0.65 0.31

triple-pane Fiberglass, Vinyl, Wood – low-e <any but air> 0.47 0.31

glass block – – – – 0.60 0.60

Warning

OpenStudio-HPXML will return an error if the combination of skylight properties is not in the above table.

HPXML Doors¶

Each opaque door is entered as an /HPXML/Building/BuildingDetails/Enclosure/Doors/Door.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

AttachedToWall idref See [102] Yes ID of attached wall

Area double ft2 > 0 Yes Total area

Azimuth or Orientation integer or string deg 0 - 359 or See [103] No See [104] Direction (clockwise from North)

RValue double F-ft2-hr/Btu > 0 Yes R-value (including any storm door)

[102] AttachedToWall must reference a Wall or FoundationWall.

[103] Orientation choices are “northeast”, “east”, “southeast”, “south”, “southwest”, “west”, “northwest”, or “north”

[104] If neither Azimuth nor Orientation nor AttachedToWall azimuth provided, defaults to the azimuth with the largest surface area defined in the HPXML file.

HPXML Partition Wall Mass¶

Partition wall mass in the conditioned space is entered as /HPXML/Building/BuildingDetails/Enclosure/extension/PartitionWallMass.

Element Type Units Constraints Required Default Notes

AreaFraction double frac >= 0 No 1.0 Fraction of both sides of wall area to conditioned floor area

InteriorFinish/Type string See [105] No gypsum board Interior finish material

InteriorFinish/Thickness double in >= 0 No 0.5 Interior finish thickness

[105] InteriorFinish/Type choices are “gypsum board”, “gypsum composite board”, “plaster”, “wood”, “other”, or “none”.

HPXML Furniture Mass¶

Furniture mass in the conditioned space is entered as /HPXML/Building/BuildingDetails/Enclosure/extension/FurnitureMass.

Element Type Units Constraints Required Default Notes

AreaFraction double frac >= 0 No 0.4 Fraction of conditioned floor area covered by furniture

Type string See [106] No light-weight Type of furniture

[106] Type choices are “light-weight” and “heavy-weight”.

Note

Light-weight furniture is modeled with a weight of 8 lb/ft2 of floor area and a density of 40 lb/ft3 while heavy-weight furniture is modeled with a weight of 16 lb/ft2 of floor area and a density of 80 lb/ft3.

HPXML Systems¶

The dwelling unit’s systems are entered in /HPXML/Building/BuildingDetails/Systems.

HPXML Heating Systems¶

Each heating system (other than a heat pump) is entered as an /HPXML/Building/BuildingDetails/Systems/HVAC/HVACPlant/HeatingSystem.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

HeatingSystemType element 1 [107] Yes Type of heating system

HeatingSystemFuel string See [108] Yes Fuel type

HeatingCapacity double Btu/hr >= 0 No autosized Heating output capacity

FractionHeatLoadServed double frac 0 - 1 [109] See [110] Fraction of heating load served

[107] HeatingSystemType child element choices are ElectricResistance, Furnace, WallFurnace, FloorFurnace, Boiler, Stove, PortableHeater, FixedHeater, Fireplace, or PackagedTerminalAirConditionerHeating.

[108] HeatingSystemFuel choices are “electricity”, “natural gas”, “fuel oil”, “fuel oil 1”, “fuel oil 2”, “fuel oil 4”, “fuel oil 5/6”, “diesel”, “propane”, “kerosene”, “coal”, “coke”, “bituminous coal”, “wood”, or “wood pellets”. For ElectricResistance, “electricity” is required. For PackagedTerminalAirConditionerHeating, “electricity” is currently the only choice.

[109] The sum of all FractionHeatLoadServed (across both HeatingSystems and HeatPumps) must be less than or equal to 1.

[110] FractionHeatLoadServed is required unless the heating system is a heat pump backup system (i.e., referenced by a HeatPump[BackupType="separate"]/BackupSystem; see HPXML Heat Pumps), in which case FractionHeatLoadServed is not allowed.

Electric Resistance¶

If electric resistance heating is specified, additional information is entered in HeatingSystem.

Element Type Units Constraints Required Default Notes

AnnualHeatingEfficiency[Units="Percent"]/Value double frac 0 - 1 No 1.0 Efficiency

PTAC Heating¶

If a PTAC with non-heat pump (e.g., electric resistance) heating is specified, additional information is entered in HeatingSystem.

Element Type Units Constraints Required Default Notes

AnnualHeatingEfficiency[Units="Percent"]/Value double frac 0 - 1 No 1.0 Efficiency

[111] A cooling system of type “packaged terminal air conditioner” must be specified in /HPXML/Building/BuildingDetails/Systems/HVAC/HVACPlant/CoolingSystem.

Furnace¶

If a furnace is specified, additional information is entered in HeatingSystem.

Element Type Units Constraints Required Default Notes

DistributionSystem idref See [111] Yes ID of attached distribution system

AnnualHeatingEfficiency[Units="AFUE"]/Value or YearInstalled double or integer frac or # 0 - 1 or > 1600 Yes See [112] Rated efficiency or Year installed

extension/FanPowerWattsPerCFM double W/cfm >= 0 No See [113] Fan efficiency at maximum airflow rate [114]

extension/AirflowDefectRatio double frac > -1 No 0.0 Deviation between design/installed airflows [115]

[112] HVACDistribution type must be AirDistribution (type: “regular velocity” or “gravity”) or DSE.

[113] If AnnualHeatingEfficiency[Units=”AFUE”]/Value not provided, defaults to 0.98 if FuelType is “electricity”, else AFUE from the lookup table that can be found at HPXMLtoOpenStudio\resources\lu_hvac_equipment_efficiency.csv based on YearInstalled.

[114] If FanPowerWattsPerCFM not provided, defaulted to 0 W/cfm if gravity distribution system, else 0.5 W/cfm if AFUE <= 0.9, else 0.375 W/cfm.

[115] If there is a cooling system attached to the DistributionSystem, the heating and cooling systems cannot have different values for FanPowerWattsPerCFM.

[116] AirflowDefectRatio is defined as (InstalledAirflow - DesignAirflow) / DesignAirflow; a value of zero means no airflow defect. See ANSI/RESNET/ACCA 310-2020 Standard for Grading the Installation of HVAC Systems for more information.

Wall/Floor Furnace¶

If a wall furnace or floor furnace is specified, additional information is entered in HeatingSystem.

Element Type Units Constraints Required Default Notes

AnnualHeatingEfficiency[Units="AFUE"]/Value or YearInstalled double or integer frac or # 0 - 1 or > 1600 Yes See [116] Rated efficiency or Year installed

extension/FanPowerWatts double W >= 0 No 0 Fan power

[117] If AnnualHeatingEfficiency[Units=”AFUE”]/Value not provided, defaults to 0.98 if FuelType is “electricity”, else AFUE from the lookup table that can be found at HPXMLtoOpenStudio\resources\lu_hvac_equipment_efficiency.csv based on YearInstalled.

Boiler¶

If a boiler is specified, additional information is entered in HeatingSystem.

Element Type Units Constraints Required Default Notes

IsSharedSystem boolean No false Whether it serves multiple dwelling units

DistributionSystem idref See [117] Yes ID of attached distribution system

AnnualHeatingEfficiency[Units="AFUE"]/Value or YearInstalled double or integer frac or # 0 - 1 or > 1600 Yes See [118] Rated efficiency or Year installed

[118] For in-unit boilers, HVACDistribution type must be HydronicDistribution (type: “radiator”, “baseboard”, “radiant floor”, or “radiant ceiling”) or DSE. For shared boilers, HVACDistribution type must be HydronicDistribution (type: “radiator”, “baseboard”, “radiant floor”, “radiant ceiling”, or “water loop”) or AirDistribution (type: “fan coil”). If the shared boiler has “water loop” distribution, a Water-Loop-to-Air Heat Pump must also be specified.

[119] If AnnualHeatingEfficiency[Units=”AFUE”]/Value not provided, defaults to 0.98 if FuelType is “electricity”, else AFUE from the lookup table that can be found at HPXMLtoOpenStudio\resources\lu_hvac_equipment_efficiency.csv based on YearInstalled.

If an in-unit boiler if specified, additional information is entered in HeatingSystem.

Element Type Units Constraints Required Default Notes

ElectricAuxiliaryEnergy double kWh/yr >= 0 No See [119] Electric auxiliary energy

[120]
If ElectricAuxiliaryEnergy not provided, defaults as follows:

Oil boiler: 330 kWh/yr

Gas boiler: 170 kWh/yr

If instead a shared boiler is specified, additional information is entered in HeatingSystem.

Element Type Units Constraints Required Default Notes

NumberofUnitsServed integer > 1 Yes Number of dwelling units served

ElectricAuxiliaryEnergy or extension/SharedLoopWatts double kWh/yr or W >= 0 No See [120] Electric auxiliary energy or shared loop power

ElectricAuxiliaryEnergy or extension/FanCoilWatts double kWh/yr or W >= 0 No [121] Electric auxiliary energy or fan coil power

[121]
If ElectricAuxiliaryEnergy nor SharedLoopWatts provided, defaults as follows:

Shared boiler w/ baseboard: 220 kWh/yr

Shared boiler w/ water loop heat pump: 265 kWh/yr

Shared boiler w/ fan coil: 438 kWh/yr

[122] FanCoilWatts only used if boiler connected to fan coil and SharedLoopWatts provided.

Stove¶

If a stove is specified, additional information is entered in HeatingSystem.

Element Type Units Constraints Required Default Notes

AnnualHeatingEfficiency[Units="Percent"]/Value double frac 0 - 1 No See [122] Efficiency

extension/FanPowerWatts double W >= 0 No 40 Fan power

[123] Defaulted to 1.0 if FuelType is “electricity”, 0.60 if FuelType is “wood”, 0.78 if FuelType is “wood pellets”, otherwise 0.81.

Portable/Fixed Heater¶

If a portable heater or fixed heater is specified, additional information is entered in HeatingSystem.

Element Type Units Constraints Required Default Notes

AnnualHeatingEfficiency[Units="Percent"]/Value double frac 0 - 1 No See [123] Efficiency

extension/FanPowerWatts double W >= 0 No 0 Fan power

[124] Defaulted to 1.0 if FuelType is “electricity”, 0.60 if FuelType is “wood”, 0.78 if FuelType is “wood pellets”, otherwise 0.81.

Fireplace¶

If a fireplace is specified, additional information is entered in HeatingSystem.

Element Type Units Constraints Required Default Notes

AnnualHeatingEfficiency[Units="Percent"]/Value double frac 0 - 1 No See [124] Efficiency

extension/FanPowerWatts double W >= 0 No 0 Fan power

[125] Defaulted to 1.0 if FuelType is “electricity”, 0.60 if FuelType is “wood”, 0.78 if FuelType is “wood pellets”, otherwise 0.81.

HPXML Cooling Systems¶

Each cooling system (other than a heat pump) is entered as an /HPXML/Building/BuildingDetails/Systems/HVAC/HVACPlant/CoolingSystem.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

CoolingSystemType string See [125] Yes Type of cooling system

CoolingSystemFuel string See [126] Yes Fuel type

FractionCoolLoadServed double frac 0 - 1 [127] Yes Fraction of cooling load served

[126] CoolingSystemType choices are “central air conditioner”, “room air conditioner”, “evaporative cooler”, “mini-split”, “chiller”, “cooling tower”, or “packaged terminal air conditioner”.

[127] CoolingSystemFuel only choice is “electricity”.

[128] The sum of all FractionCoolLoadServed (across both CoolingSystems and HeatPumps) must be less than or equal to 1.

Central Air Conditioner¶

If a central air conditioner is specified, additional information is entered in CoolingSystem.

Element Type Units Constraints Required Default Notes

DistributionSystem idref See [128] Yes ID of attached distribution system

AnnualCoolingEfficiency[Units="SEER"]/Value or YearInstalled double or integer Btu/Wh or # > 0 or > 1600 Yes See [129] Rated efficiency or Year installed

CoolingCapacity double Btu/hr >= 0 No autosized Cooling output capacity

SensibleHeatFraction double frac 0 - 1 No Sensible heat fraction

CompressorType string See [130] No See [131] Type of compressor

extension/FanPowerWattsPerCFM double W/cfm >= 0 No See [132] Fan efficiency at maximum airflow rate [133]

extension/AirflowDefectRatio double frac > -1 No 0.0 Deviation between design/installed airflows [134]

extension/ChargeDefectRatio double frac > -1 No 0.0 Deviation between design/installed charges [135]

[129] HVACDistribution type must be AirDistribution (type: “regular velocity”) or DSE.

[130] If AnnualCoolingEfficiency[Units=”SEER”]/Value not provided, defaults to SEER from the lookup table that can be found at HPXMLtoOpenStudio\resources\lu_hvac_equipment_efficiency.csv based on YearInstalled.

[131] CompressorType choices are “single stage”, “two stage”, or “variable speed”.

[132] If CompressorType not provided, defaults to “single stage” if SEER <= 15, else “two stage” if SEER <= 21, else “variable speed”.

[133] If FanPowerWattsPerCFM not provided, defaults to using attached furnace W/cfm if available, else 0.5 W/cfm if SEER <= 13.5, else 0.375 W/cfm.

[134] If there is a heating system attached to the DistributionSystem, the heating and cooling systems cannot have different values for FanPowerWattsPerCFM.

[135] AirflowDefectRatio is defined as (InstalledAirflow - DesignAirflow) / DesignAirflow; a value of zero means no airflow defect. See ANSI/RESNET/ACCA 310-2020 Standard for Grading the Installation of HVAC Systems for more information.

[136] ChargeDefectRatio is defined as (InstalledCharge - DesignCharge) / DesignCharge; a value of zero means no refrigerant charge defect. A non-zero charge defect should typically only be applied for systems that are pre-charged on site. See ANSI/RESNET/ACCA 310-2020 Standard for Grading the Installation of HVAC Systems for more information.

Room Air Conditioner¶

If a room air conditioner is specified, additional information is entered in CoolingSystem.

Element Type Units Constraints Required Default Notes

AnnualCoolingEfficiency[Units="EER" or Units="CEER"]/Value or YearInstalled double or integer Btu/Wh or # > 0 or > 1600 Yes See [136] Rated efficiency or Year installed

CoolingCapacity double Btu/hr >= 0 No autosized Cooling output capacity

SensibleHeatFraction double frac 0 - 1 No Sensible heat fraction

[137] If AnnualCoolingEfficiency[Units=”EER” or Units=”CEER”]/Value not provided, defaults to EER from the lookup table that can be found at HPXMLtoOpenStudio\resources\lu_hvac_equipment_efficiency.csv based on YearInstalled.

Packaged Terminal Air Conditioner¶

If a PTAC is specified, additional information is entered in CoolingSystem.

Element Type Units Constraints Required Default Notes

AnnualCoolingEfficiency[Units="EER" or Units="CEER"]/Value integer or double # or Btu/Wh > 1600 or > 0 Yes Rated efficiency

CoolingCapacity double Btu/hr >= 0 No autosized Cooling output capacity

SensibleHeatFraction double frac 0 - 1 No Sensible heat fraction

Evaporative Cooler¶

If an evaporative cooler is specified, additional information is entered in CoolingSystem.

Element Type Units Constraints Required Default Notes

DistributionSystem idref See [137] No ID of attached distribution system

CoolingCapacity double Btu/hr >= 0 No autosized Cooling output capacity

[138] If provided, HVACDistribution type must be AirDistribution (type: “regular velocity”) or DSE.

Mini-Split¶

If a mini-split is specified, additional information is entered in CoolingSystem.

Element Type Units Constraints Required Default Notes

DistributionSystem idref See [138] No ID of attached distribution system

AnnualCoolingEfficiency[Units="SEER"]/Value double Btu/Wh > 0 Yes Rated cooling efficiency

CoolingCapacity double Btu/hr >= 0 No autosized Cooling output capacity

SensibleHeatFraction double frac 0 - 1 No Sensible heat fraction

extension/FanPowerWattsPerCFM double W/cfm >= 0 No See [139] Fan efficiency at maximum airflow rate

extension/AirflowDefectRatio double frac > -1 No 0.0 Deviation between design/installed airflows [140]

extension/ChargeDefectRatio double frac > -1 No 0.0 Deviation between design/installed charges [141]

[139] If provided, HVACDistribution type must be AirDistribution (type: “regular velocity”) or DSE.

[140] FanPowerWattsPerCFM defaults to 0.07 W/cfm for ductless systems and 0.18 W/cfm for ducted systems.

[141] AirflowDefectRatio is defined as (InstalledAirflow - DesignAirflow) / DesignAirflow; a value of zero means no airflow defect. A non-zero airflow defect should typically only be applied for systems attached to ducts. See ANSI/RESNET/ACCA 310-2020 Standard for Grading the Installation of HVAC Systems for more information.

[142] ChargeDefectRatio is defined as (InstalledCharge - DesignCharge) / DesignCharge; a value of zero means no refrigerant charge defect. A non-zero charge defect should typically only be applied for systems that are pre-charged on site. See ANSI/RESNET/ACCA 310-2020 Standard for Grading the Installation of HVAC Systems for more information.

Chiller¶

If a chiller is specified, additional information is entered in CoolingSystem.

Element Type Units Constraints Required Default Notes

IsSharedSystem boolean true Yes Whether it serves multiple dwelling units

DistributionSystem idref See [142] Yes ID of attached distribution system

NumberofUnitsServed integer > 1 Yes Number of dwelling units served

CoolingCapacity double Btu/hr >= 0 Yes Total cooling output capacity

AnnualCoolingEfficiency[Units="kW/ton"]/Value double kW/ton > 0 Yes Rated efficiency

extension/SharedLoopWatts double W >= 0 Yes Pumping and fan power serving the system

extension/FanCoilWatts double W >= 0 See [143] Fan coil power

[143] HVACDistribution type must be HydronicDistribution (type: “radiator”, “baseboard”, “radiant floor”, “radiant ceiling”, or “water loop”) or AirDistribution (type: “fan coil”). If the chiller has “water loop” distribution, a Water-Loop-to-Air Heat Pump must also be specified.

[144] FanCoilWatts only required if chiller connected to fan coil.

Note

Chillers are modeled as central air conditioners with a SEER equivalent using the equation from ANSI/RESNET/ICC 301-2019.

Cooling Tower¶

If a cooling tower is specified, additional information is entered in CoolingSystem.

Element Type Units Constraints Required Default Notes

IsSharedSystem boolean true Yes Whether it serves multiple dwelling units

DistributionSystem idref See [144] Yes ID of attached distribution system

NumberofUnitsServed integer > 1 Yes Number of dwelling units served

extension/SharedLoopWatts double W >= 0 Yes Pumping and fan power serving the system

[145] HVACDistribution type must be HydronicDistribution (type: “water loop”). A Water-Loop-to-Air Heat Pump must also be specified.

Note

Cooling towers w/ water loop heat pumps are modeled as central air conditioners with a SEER equivalent using the equation from ANSI/RESNET/ICC 301-2019.

HPXML Heat Pumps¶

Each heat pump is entered as an /HPXML/Building/BuildingDetails/Systems/HVAC/HVACPlant/HeatPump.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

HeatPumpType string See [145] Yes Type of heat pump

HeatPumpFuel string See [146] Yes Fuel type

BackupType string See [147] No <none> Type of backup heating

[146] HeatPumpType choices are “air-to-air”, “mini-split”, “ground-to-air”, “water-loop-to-air”, or “packaged terminal heat pump”.

[147] HeatPumpFuel only choice is “electricity”.

[148] BackupType choices are “integrated” or “separate”. Use “integrated” if the heat pump’s distribution system and blower fan power applies to the backup heating (e.g., built-in electric strip heat or an integrated backup furnace, i.e., a dual-fuel heat pump). Use “separate” if the backup system has its own distribution system (e.g., electric baseboard or a boiler).

If a backup type of “integrated” is provided, additional information is entered in HeatPump.

Element Type Units Constraints Required Default Notes

BackupSystemFuel string See [148] Yes Integrated backup heating fuel type

BackupAnnualHeatingEfficiency[Units="Percent" or Units="AFUE"]/Value double frac 0 - 1 Yes Integrated backup heating efficiency

BackupHeatingCapacity double Btu/hr >= 0 No autosized Integrated backup heating output capacity

BackupHeatingSwitchoverTemperature double F No <none> Integrated backup heating switchover temperature [149]

[149] BackupSystemFuel choices are “electricity”, “natural gas”, “fuel oil”, “fuel oil 1”, “fuel oil 2”, “fuel oil 4”, “fuel oil 5/6”, “diesel”, “propane”, “kerosene”, “coal”, “coke”, “bituminous coal”, “wood”, or “wood pellets”.

[150] Provide BackupHeatingSwitchoverTemperature for a situation in which there is a discrete outdoor temperature when the heat pump stops operating and the backup heating system starts operating. If not provided, the backup heating system will operate as needed for hours when the heat pump has insufficient capacity.

If a backup type of “separate” is provided, additional information is entered in HeatPump.

Element Type Units Constraints Required Default Notes

BackupSystem idref See [150] Yes ID of separate backup heating system

BackupHeatingSwitchoverTemperature double F No <none> Separate backup heating system switchover temperature [151]

[151] HeatingSystem must be of type ElectricResistance, WallFurnace, FloorFurnace, Boiler, Stove, PortableHeater, FixedHeater, or Fireplace.

[152] Provide BackupHeatingSwitchoverTemperature for a situation in which there is a discrete outdoor temperature when the heat pump stops operating and the backup heating system starts operating. If not provided, the backup heating system will operate as needed for hours when the heat pump has insufficient capacity.

Note

Due to how the separate backup heating system is modeled in EnergyPlus, there are a few restrictions:

The conditioned space cannot be partially heated (i.e., the sum of all FractionHeatLoadServed must be 1).

There cannot be multiple backup heating systems.

Air-to-Air Heat Pump¶

If an air-to-air heat pump is specified, additional information is entered in HeatPump.

Element Type Units Constraints Required Default Notes

DistributionSystem idref See [152] Yes ID of attached distribution system

CompressorType string See [153] No See [154] Type of compressor

HeatingCapacity double Btu/hr >= 0 No autosized Heating output capacity (excluding any backup heating)

HeatingCapacity17F double Btu/hr >= 0, <= HeatingCapacity No Heating output capacity at 17F, if available

CoolingCapacity double Btu/hr >= 0 No autosized Cooling output capacity

CoolingSensibleHeatFraction double frac 0 - 1 No Sensible heat fraction

FractionHeatLoadServed double frac 0 - 1 [155] Yes Fraction of heating load served

FractionCoolLoadServed double frac 0 - 1 [156] Yes Fraction of cooling load served

AnnualCoolingEfficiency[Units="SEER"]/Value or YearInstalled double or integer Btu/Wh or # > 0 or > 1600 Yes See [157] Rated cooling efficiency or Year installed

AnnualHeatingEfficiency[Units="HSPF"]/Value or YearInstalled double or integer Btu/Wh or # > 0 or > 1600 Yes See [158] Rated heating efficiency or Year installed

extension/FanPowerWattsPerCFM double W/cfm >= 0 No See [159] Fan efficiency at maximum airflow rate

extension/AirflowDefectRatio double frac > -1 No 0.0 Deviation between design/installed airflows [160]

extension/ChargeDefectRatio double frac > -1 No 0.0 Deviation between design/installed charges [161]

[153] HVACDistribution type must be AirDistribution (type: “regular velocity”) or DSE.

[154] CompressorType choices are “single stage”, “two stage”, or “variable speed”.

[155] If CompressorType not provided, defaults to “single stage” if SEER <= 15, else “two stage” if SEER <= 21, else “variable speed”.

[156] The sum of all FractionHeatLoadServed (across both HeatingSystems and HeatPumps) must be less than or equal to 1.

[157] The sum of all FractionCoolLoadServed (across both CoolingSystems and HeatPumps) must be less than or equal to 1.

[158] If AnnualCoolingEfficiency[Units=”SEER”]/Value not provided, defaults to SEER from the lookup table that can be found at HPXMLtoOpenStudio\resources\lu_hvac_equipment_efficiency.csv based on YearInstalled.

[159] If AnnualHeatingEfficiency[Units=”HSPF”]/Value not provided, defaults to HSPF from the lookup table that can be found at HPXMLtoOpenStudio\resources\lu_hvac_equipment_efficiency.csv based on YearInstalled.

[160] If FanPowerWattsPerCFM not provided, defaulted to 0.5 W/cfm if HSPF <= 8.75, else 0.375 W/cfm.

[161] AirflowDefectRatio is defined as (InstalledAirflow - DesignAirflow) / DesignAirflow; a value of zero means no airflow defect. See ANSI/RESNET/ACCA 310-2020 Standard for Grading the Installation of HVAC Systems for more information.

[162] ChargeDefectRatio is defined as (InstalledCharge - DesignCharge) / DesignCharge; a value of zero means no refrigerant charge defect. A non-zero charge defect should typically only be applied for systems that are pre-charged on site. See ANSI/RESNET/ACCA 310-2020 Standard for Grading the Installation of HVAC Systems for more information.

Mini-Split Heat Pump¶

If a mini-split heat pump is specified, additional information is entered in HeatPump.

Element Type Units Constraints Required Default Notes

DistributionSystem idref See [162] No ID of attached distribution system, if present

HeatingCapacity double Btu/hr >= 0 No autosized Heating output capacity (excluding any backup heating)

HeatingCapacity17F double Btu/hr >= 0, <= HeatingCapacity No Heating output capacity at 17F, if available

CoolingCapacity double Btu/hr >= 0 No autosized Cooling output capacity

CoolingSensibleHeatFraction double frac 0 - 1 No Sensible heat fraction

FractionHeatLoadServed double frac 0 - 1 [163] Yes Fraction of heating load served

FractionCoolLoadServed double frac 0 - 1 [164] Yes Fraction of cooling load served

AnnualCoolingEfficiency[Units="SEER"]/Value double Btu/Wh > 0 Yes Rated cooling efficiency

AnnualHeatingEfficiency[Units="HSPF"]/Value double Btu/Wh > 0 Yes Rated heating efficiency

extension/FanPowerWattsPerCFM double W/cfm >= 0 No See [165] Fan efficiency at maximum airflow rate

extension/AirflowDefectRatio double frac > -1 No 0.0 Deviation between design/installed airflows [166]

extension/ChargeDefectRatio double frac > -1 No 0.0 Deviation between design/installed charges [167]

[163] If provided, HVACDistribution type must be AirDistribution (type: “regular velocity”) or DSE.

[164] The sum of all FractionHeatLoadServed (across both HeatingSystems and HeatPumps) must be less than or equal to 1.

[165] The sum of all FractionCoolLoadServed (across both CoolingSystems and HeatPumps) must be less than or equal to 1.

[166] FanPowerWattsPerCFM defaults to 0.07 W/cfm for ductless systems and 0.18 W/cfm for ducted systems.

[167] AirflowDefectRatio is defined as (InstalledAirflow - DesignAirflow) / DesignAirflow; a value of zero means no airflow defect. A non-zero airflow defect should typically only be applied for systems attached to ducts. See ANSI/RESNET/ACCA 310-2020 Standard for Grading the Installation of HVAC Systems for more information.

[168] ChargeDefectRatio is defined as (InstalledCharge - DesignCharge) / DesignCharge; a value of zero means no refrigerant charge defect. A non-zero charge defect should typically only be applied for systems that are pre-charged on site. See ANSI/RESNET/ACCA 310-2020 Standard for Grading the Installation of HVAC Systems for more information.

Packaged Terminal Heat Pump¶

If a packaged terminal heat pump is specified, additional information is entered in HeatPump.

Element Type Units Constraints Required Default Notes

HeatingCapacity double Btu/hr >= 0 No autosized Heating output capacity (excluding any backup heating)

CoolingCapacity double Btu/hr >= 0 No autosized Cooling output capacity

CoolingSensibleHeatFraction double frac 0 - 1 No Sensible heat fraction

FractionHeatLoadServed double frac 0 - 1 [168] Yes Fraction of heating load served

FractionCoolLoadServed double frac 0 - 1 [169] Yes Fraction of cooling load served

AnnualCoolingEfficiency[Units="EER" or Units="CEER"]/Value double Btu/Wh > 0 Yes Rated cooling efficiency

AnnualHeatingEfficiency[Units="COP"]/Value double Btu/Wh > 0 Yes Rated heating efficiency

[169] The sum of all FractionHeatLoadServed (across both HeatingSystems and HeatPumps) must be less than or equal to 1.

[170] The sum of all FractionCoolLoadServed (across both CoolingSystems and HeatPumps) must be less than or equal to 1.

Ground-to-Air Heat Pump¶

If a ground-to-air heat pump is specified, additional information is entered in HeatPump.

Element Type Units Constraints Required Default Notes

IsSharedSystem boolean No false Whether it has a shared hydronic circulation loop [170]

DistributionSystem idref See [171] Yes ID of attached distribution system

HeatingCapacity double Btu/hr >= 0 No autosized Heating output capacity (excluding any backup heating)

CoolingCapacity double Btu/hr >= 0 No autosized Cooling output capacity

CoolingSensibleHeatFraction double frac 0 - 1 No Sensible heat fraction

FractionHeatLoadServed double frac 0 - 1 [172] Yes Fraction of heating load served

FractionCoolLoadServed double frac 0 - 1 [173] Yes Fraction of cooling load served

AnnualCoolingEfficiency[Units="EER"]/Value double Btu/Wh > 0 Yes Rated cooling efficiency

AnnualHeatingEfficiency[Units="COP"]/Value double W/W > 0 Yes Rated heating efficiency

NumberofUnitsServed integer > 0 See [174] Number of dwelling units served

extension/PumpPowerWattsPerTon double W/ton >= 0 No See [175] Pump power [176]

extension/SharedLoopWatts double W >= 0 See [177] Shared pump power [178]

extension/FanPowerWattsPerCFM double W/cfm >= 0 No See [179] Fan efficiency at maximum airflow rate

extension/AirflowDefectRatio double frac > -1 No 0.0 Deviation between design/installed airflows [180]

extension/ChargeDefectRatio double frac > -1 No 0.0 Deviation between design/installed charges [181]

[171] IsSharedSystem should be true if the SFA/MF building has multiple ground source heat pumps connected to a shared hydronic circulation loop.

[172] HVACDistribution type must be AirDistribution (type: “regular velocity”) or DSE.

[173] The sum of all FractionHeatLoadServed (across both HeatingSystems and HeatPumps) must be less than or equal to 1.

[174] The sum of all FractionCoolLoadServed (across both CoolingSystems and HeatPumps) must be less than or equal to 1.

[175] NumberofUnitsServed only required if IsSharedSystem is true, in which case it must be > 1.

[176] If PumpPowerWattsPerTon not provided, defaults to 30 W/ton per ANSI/RESNET/ICC 301-2019 for a closed loop system.

[177] Pump power is calculated using PumpPowerWattsPerTon and the cooling capacity in tons, unless the system only provides heating, in which case the heating capacity in tons is used instead. Any pump power that is shared by multiple dwelling units should be included in SharedLoopWatts, not PumpPowerWattsPerTon, so that shared loop pump power attributed to the dwelling unit is calculated.

[178] SharedLoopWatts only required if IsSharedSystem is true.

[179] Shared loop pump power attributed to the dwelling unit is calculated as SharedLoopWatts / NumberofUnitsServed.

[180] If FanPowerWattsPerCFM not provided, defaulted to 0.5 W/cfm if COP <= 8.75/3.2, else 0.375 W/cfm.

[181] AirflowDefectRatio is defined as (InstalledAirflow - DesignAirflow) / DesignAirflow; a value of zero means no airflow defect. See ANSI/RESNET/ACCA 310-2020 Standard for Grading the Installation of HVAC Systems for more information.

[182] ChargeDefectRatio is defined as (InstalledCharge - DesignCharge) / DesignCharge; a value of zero means no refrigerant charge defect. A non-zero charge defect should typically only be applied for systems that are pre-charged on site. See ANSI/RESNET/ACCA 310-2020 Standard for Grading the Installation of HVAC Systems for more information.

Water-Loop-to-Air Heat Pump¶

If a water-loop-to-air heat pump is specified, additional information is entered in HeatPump.

Element Type Units Constraints Required Default Notes

DistributionSystem idref See [182] Yes ID of attached distribution system

HeatingCapacity double Btu/hr > 0 No autosized Heating output capacity

CoolingCapacity double Btu/hr > 0 See [183] Cooling output capacity

AnnualCoolingEfficiency[Units="EER"]/Value double Btu/Wh > 0 See [184] Rated cooling efficiency

AnnualHeatingEfficiency[Units="COP"]/Value double W/W > 0 See [185] Rated heating efficiency

[183] HVACDistribution type must be AirDistribution (type: “regular velocity”) or DSE.

[184] CoolingCapacity required if there is a shared chiller or cooling tower with water loop distribution.

[185] AnnualCoolingEfficiency required if there is a shared chiller or cooling tower with water loop distribution.

[186] AnnualHeatingEfficiency required if there is a shared boiler with water loop distribution.

Note

If a water loop heat pump is specified, there must be at least one shared heating system (i.e., Boiler) and/or one shared cooling system (i.e., Chiller or Cooling Tower) specified with water loop distribution.

HPXML HVAC Control¶

If any HVAC systems are specified, a single thermostat is entered as a /HPXML/Building/BuildingDetails/Systems/HVAC/HVACControl.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

HeatingSeason element No See [186] Heating season

CoolingSeason element No See [187] Cooling season

extension/CeilingFanSetpointTempCoolingSeasonOffset double F >= 0 No 0 Cooling setpoint temperature offset [188]

[187] If HeatingSeason not provided, defaults to year-round.

[188] If CoolingSeason not provided, defaults to year-round.

[189] CeilingFanSetpointTempCoolingSeasonOffset should only be used if there are sufficient ceiling fans present to warrant a reduced cooling setpoint.

If a heating and/or cooling season is defined, additional information is entered in HVACControl/HeatingSeason and/or HVACControl/CoolingSeason.

Element Type Units Constraints Required Default Description

BeginMonth integer 1 - 12 Yes Begin month

BeginDayOfMonth integer 1 - 31 Yes Begin day

EndMonth integer 1 - 12 Yes End month

EndDayOfMonth integer 1 - 31 Yes End day

Heating and cooling seasons, when combined, must span the entire year.

Thermostat setpoints are additionally entered using either simple inputs or detailed inputs.

Simple Inputs¶

To define simple thermostat setpoints, additional information is entered in HVACControl.

Element Type Units Constraints Required Default Notes

SetpointTempHeatingSeason double F See [189] Heating setpoint temperature

SetpointTempCoolingSeason double F See [190] Cooling setpoint temperature

[190] SetpointTempHeatingSeason only required if there is heating equipment (i.e., sum of all FractionHeatLoadServed is greater than 0).

[191] SetpointTempCoolingSeason only required if there is cooling equipment (i.e., sum of all FractionCoolLoadServed is greater than 0).

If there is a heating temperature setback, additional information is entered in HVACControl.

Element Type Units Constraints Required Default Notes

SetbackTempHeatingSeason double F Yes Heating setback temperature

TotalSetbackHoursperWeekHeating integer hrs/week > 0 Yes Hours/week of heating temperature setback [191]

extension/SetbackStartHourHeating integer 0 - 23 No 23 (11pm) Daily setback start hour

[192] TotalSetbackHoursperWeekHeating is converted to hrs/day and modeled as a temperature setback every day starting at SetbackStartHourHeating.

If there is a cooling temperature setup, additional information is entered in HVACControl.

Element Type Units Constraints Required Default Notes

SetupTempCoolingSeason double F Yes Cooling setup temperature

TotalSetupHoursperWeekCooling integer hrs/week > 0 Yes Hours/week of cooling temperature setup [192]

extension/SetupStartHourCooling integer 0 - 23 No 9 (9am) Daily setup start hour

[193] TotalSetupHoursperWeekCooling is converted to hrs/day and modeled as a temperature setup every day starting at SetupStartHourCooling.

Detailed Inputs¶

To define detailed thermostat setpoints, additional information is entered in HVACControl.

Element Type Units Constraints Required Default Notes

extension/WeekdaySetpointTempsHeatingSeason array F See [193] 24 comma-separated weekday heating setpoints

extension/WeekendSetpointTempsHeatingSeason array F See [194] 24 comma-separated weekend heating setpoints

extension/WeekdaySetpointTempsCoolingSeason array F See [195] 24 comma-separated weekday cooling setpoints

extension/WeekendSetpointTempsCoolingSeason array F See [196] 24 comma-separated weekend cooling setpoints

[194] WeekdaySetpointTempsHeatingSeason only required if there is heating equipment (i.e., sum of all FractionHeatLoadServed is greater than 0).

[195] WeekendSetpointTempsHeatingSeason only required if there is heating equipment (i.e., sum of all FractionHeatLoadServed is greater than 0).

[196] WeekdaySetpointTempsCoolingSeason only required if there is cooling equipment (i.e., sum of all FractionCoolLoadServed is greater than 0).

[197] WeekendSetpointTempsCoolingSeason only required if there is cooling equipment (i.e., sum of all FractionCoolLoadServed is greater than 0).

HPXML HVAC Distribution¶

Each separate HVAC distribution system is entered as a /HPXML/Building/BuildingDetails/Systems/HVAC/HVACDistribution.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

DistributionSystemType element 1 [197] Yes Type of distribution system

ConditionedFloorAreaServed double ft2 > 0 See [198] Conditioned floor area served

[198] DistributionSystemType child element choices are AirDistribution, HydronicDistribution, or Other=DSE.

[199] ConditionedFloorAreaServed required only when DistributionSystemType is AirDistribution and AirDistribution/Ducts are present.

Note

There should be at most one heating system and one cooling system attached to a distribution system. See HPXML Heating Systems, HPXML Cooling Systems, and HPXML Heat Pumps for information on which DistributionSystemType is allowed for which HVAC system. Also note that some HVAC systems (e.g., room air conditioners) are not allowed to be attached to a distribution system.

Air Distribution¶

To define an air distribution system, additional information is entered in HVACDistribution/DistributionSystemType/AirDistribution.

Element Type Units Constraints Required Default Notes

AirDistributionType string See [199] Yes Type of air distribution

DuctLeakageMeasurement[DuctType="supply"] element 1 See [200] Supply duct leakage value

DuctLeakageMeasurement[DuctType="return"] element 1 See [201] Return duct leakage value

Ducts element >= 0 No Supply/return ducts [202]

NumberofReturnRegisters integer >= 0 No See [203] Number of return registers

[200] AirDistributionType choices are “regular velocity”, “gravity”, or “fan coil” and are further restricted based on attached HVAC system type (e.g., only “regular velocity” or “gravity” for a furnace, only “fan coil” for a shared boiler, etc.).

[201] Supply duct leakage required if AirDistributionType is “regular velocity” or “gravity” and optional if AirDistributionType is “fan coil”.

[202] Return duct leakage required if AirDistributionType is “regular velocity” or “gravity” and optional if AirDistributionType is “fan coil”.

[203] Provide a Ducts element for each supply duct and each return duct.

[204] If NumberofReturnRegisters not provided and AirDistribution/Ducts are present, defaults to one return register per conditioned floor per ASHRAE Standard 152, rounded up to the nearest integer if needed.

Additional information is entered in each DuctLeakageMeasurement.

Element Type Units Constraints Required Default Notes

DuctLeakage/Units string See [204] Yes Duct leakage units

DuctLeakage/Value double >= 0 [205] Yes Duct leakage value [206]

DuctLeakage/TotalOrToOutside string See [207] Yes Type of duct leakage (outside conditioned space vs total)

[205] Units choices are “CFM25”, “CFM50”, or “Percent”.

[206] Value also must be < 1 if Units is Percent.

[207] If the HVAC system has no return ducts (e.g., a ducted evaporative cooler), use zero for the Value.

[208] TotalOrToOutside only choice is “to outside”.

Additional information is entered in each Ducts.

Element Type Units Constraints Required Default Notes

DuctInsulationRValue double F-ft2-hr/Btu >= 0 Yes R-value of duct insulation [208]

DuctLocation string See [209] No See [210] Duct location

FractionDuctArea and/or DuctSurfaceArea double frac or ft2 0-1 [211] or >= 0 See [212] See [213] Duct fraction/surface area in location

[209] DuctInsulationRValue should not include air films (i.e., use 0 for an uninsulated duct).

[210] DuctLocation choices are “living space”, “basement - conditioned”, “basement - unconditioned”, “crawlspace - unvented”, “crawlspace - vented”, “crawlspace - conditioned”, “attic - unvented”, “attic - vented”, “garage”, “outside”, “exterior wall”, “under slab”, “roof deck”, “other housing unit”, “other heated space”, “other multifamily buffer space”, or “other non-freezing space”. See HPXML Locations for descriptions.

[211] If DuctLocation not provided, defaults to the first present space type: “basement - conditioned”, “basement - unconditioned”, “crawlspace - conditioned”, “crawlspace - vented”, “crawlspace - unvented”, “attic - vented”, “attic - unvented”, “garage”, or “living space”. If NumberofConditionedFloorsAboveGrade > 1, secondary ducts will be located in “living space”.

[212] The sum of all [DuctType="supply"]/FractionDuctArea and [DuctType="return"]/FractionDuctArea must each equal to 1.

[213] Either FractionDuctArea or DuctSurfaceArea (or both) are required if DuctLocation is provided.

[214]
If DuctSurfaceArea not provided, duct surface areas will be calculated based on FractionDuctArea if provided. If FractionDuctArea also not provided, duct surface areas will be calculated based on ASHRAE Standard 152:

Primary supply ducts: 0.27 * F_out * ConditionedFloorAreaServed

Secondary supply ducts: 0.27 * (1 - F_out) * ConditionedFloorAreaServed

Primary return ducts: b_r * F_out * ConditionedFloorAreaServed

Secondary return ducts: b_r * (1 - F_out) * ConditionedFloorAreaServed

where F_out is 1.0 when NumberofConditionedFloorsAboveGrade <= 1 and 0.75 when NumberofConditionedFloorsAboveGrade > 1, and b_r is 0.05 * NumberofReturnRegisters with a maximum value of 0.25.

Hydronic Distribution¶

To define a hydronic distribution system, additional information is entered in HVACDistribution/DistributionSystemType/HydronicDistribution.

Element Type Units Constraints Required Default Notes

HydronicDistributionType string See [214] Yes Type of hydronic distribution system

[215] HydronicDistributionType choices are “radiator”, “baseboard”, “radiant floor”, or “radiant ceiling”.

Distribution System Efficiency (DSE)¶

Warning

A simplified DSE model is provided for flexibility, but it is strongly recommended to use one of the other detailed distribution system types for better accuracy. Also note that when specifying a DSE system, its effect is reflected in the Workflow Outputs but is not reflected in the raw EnergyPlus simulation outputs.

To define a DSE system, additional information is entered in HVACDistribution.

Element Type Units Constraints Required Default Notes

AnnualHeatingDistributionSystemEfficiency double frac 0 - 1 Yes Seasonal distribution system efficiency for heating

AnnualCoolingDistributionSystemEfficiency double frac 0 - 1 Yes Seasonal distribution system efficiency for cooling

DSE values can be calculated from ASHRAE Standard 152.

HPXML Whole Ventilation Fan¶

Each mechanical ventilation system that provides ventilation to the whole dwelling unit is entered as a /HPXML/Building/BuildingDetails/Systems/MechanicalVentilation/VentilationFans/VentilationFan. If not entered, the simulation will not include mechanical ventilation.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

UsedForWholeBuildingVentilation boolean true Yes Must be set to true

IsSharedSystem boolean See [215] No false Whether it serves multiple dwelling units

FanType string See [216] Yes Type of ventilation system

RatedFlowRate or TestedFlowRate or CalculatedFlowRate or DeliveredVentilation double cfm >= 0 No See [217] Flow rate [218]

HoursInOperation double hrs/day 0 - 24 No See [219] Hours per day of operation

FanPower double W >= 0 No See [220] Fan power

[216] For central fan integrated supply systems, IsSharedSystem must be false.

[217] FanType choices are “energy recovery ventilator”, “heat recovery ventilator”, “exhaust only”, “supply only”, “balanced”, or “central fan integrated supply”.

[218] If flow rate not provided, defaults to the required mechanical ventilation rate per ASHRAE 62.2-2019, including adjustments for A) infiltration credit, B) balanced vs imbalanced systems, and C) adiabatic surfaces for SFA/MF buildings.

[219] For a central fan integrated supply system, the flow rate should equal the amount of outdoor air provided to the distribution system.

[220] If HoursInOperation not provided, defaults to 24 (i.e., running continuously) for all system types other than central fan integrated supply (CFIS), and 8.0 (i.e., running intermittently) for CFIS systems.

[221]
If FanPower not provided, defaults based on ANSI/RESNET/ICC 301-2019:

“energy recovery ventilator”, “heat recovery ventilator”, or shared system: 1.0 W/cfm

“balanced”: 0.7 W/cfm

“central fan integrated supply”: 0.5 W/cfm

“exhaust only” or “supply only”: 0.35 W/cfm

Exhaust/Supply Only¶

If a supply only or exhaust only system is specified, no additional information is entered.

Balanced¶

If a balanced system is specified, no additional information is entered.

Heat Recovery Ventilator¶

If a heat recovery ventilator system is specified, additional information is entered in VentilationFan.

Element Type Units Constraints Required Default Notes

SensibleRecoveryEfficiency or AdjustedSensibleRecoveryEfficiency double frac 0 - 1 Yes (Adjusted) Sensible recovery efficiency

Energy Recovery Ventilator¶

If an energy recovery ventilator system is specified, additional information is entered in VentilationFan.

Element Type Units Constraints Required Default Notes

TotalRecoveryEfficiency or AdjustedTotalRecoveryEfficiency double frac 0 - 1 Yes (Adjusted) Total recovery efficiency

SensibleRecoveryEfficiency or AdjustedSensibleRecoveryEfficiency double frac 0 - 1 Yes (Adjusted) Sensible recovery efficiency

Central Fan Integrated Supply¶

If a central fan integrated supply system is specified, additional information is entered in VentilationFan.

Element Type Units Constraints Required Default Notes

AttachedToHVACDistributionSystem idref See [221] Yes ID of attached distribution system

[222] HVACDistribution type cannot be HydronicDistribution.

Shared System¶

If the specified system is a shared system (i.e., serving multiple dwelling units), additional information is entered in VentilationFan.

Element Type Units Constraints Required Default Notes

FractionRecirculation double frac 0 - 1 Yes Fraction of supply air that is recirculated [222]

extension/InUnitFlowRate double cfm >= 0 [223] Yes Flow rate delivered to the dwelling unit

extension/PreHeating element 0 - 1 No <none> Supply air preconditioned by heating equipment? [224]

extension/PreCooling element 0 - 1 No <none> Supply air preconditioned by cooling equipment? [225]

[223] 1-FractionRecirculation is assumed to be the fraction of supply air that is provided from outside. The value must be 0 for exhaust only systems.

[224] InUnitFlowRate must also be < (RatedFlowRate or TestedFlowRate or CalculatedFlowRate or DeliveredVentilation).

[225] PreHeating not allowed for exhaust only systems.

[226] PreCooling not allowed for exhaust only systems.

If pre-heating is specified, additional information is entered in extension/PreHeating.

Element Type Units Constraints Required Default Notes

Fuel string See [226] Yes Pre-heating equipment fuel type

AnnualHeatingEfficiency[Units="COP"]/Value double W/W > 0 Yes Pre-heating equipment annual COP

FractionVentilationHeatLoadServed double frac 0 - 1 Yes Fraction of ventilation heating load served by pre-heating equipment

[227] Fuel choices are “natural gas”, “fuel oil”, “fuel oil 1”, “fuel oil 2”, “fuel oil 4”, “fuel oil 5/6”, “diesel”, “propane”, “kerosene”, “coal”, “coke”, “bituminous coal”, “anthracite coal”, “electricity”, “wood”, or “wood pellets”.

If pre-cooling is specified, additional information is entered in extension/PreCooling.

Element Type Units Constraints Required Default Notes

Fuel string See [227] Yes Pre-cooling equipment fuel type

AnnualCoolingEfficiency[Units="COP"]/Value double W/W > 0 Yes Pre-cooling equipment annual COP

FractionVentilationCoolLoadServed double frac 0 - 1 Yes Fraction of ventilation cooling load served by pre-cooling equipment

[228] Fuel only choice is “electricity”.

HPXML Local Ventilation Fan¶

Each kitchen range fan or bathroom fan that provides local ventilation is entered as a /HPXML/Building/BuildingDetails/Systems/MechanicalVentilation/VentilationFans/VentilationFan. If not entered, the simulation will not include kitchen/bathroom fans.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

UsedForLocalVentilation boolean true Yes Must be set to true

Quantity integer >= 0 No See [228] Number of identical fans

RatedFlowRate or TestedFlowRate or CalculatedFlowRate or DeliveredVentilation double cfm >= 0 No See [229] Flow rate

HoursInOperation double hrs/day 0 - 24 No See [230] Hours per day of operation

FanLocation string See [231] Yes Location of the fan

FanPower double W >= 0 No See [232] Fan power

extension/StartHour integer 0 - 23 No See [233] Daily start hour of operation

[229] If Quantity not provided, defaults to 1 for kitchen fans and NumberofBathrooms for bath fans based on the 2010 BAHSP.

[230] If flow rate not provided, defaults to 100 cfm for kitchen fans and 50 cfm for bath fans based on the 2010 BAHSP.

[231] If HoursInOperation not provided, defaults to 1 based on the 2010 BAHSP.

[232] FanLocation choices are “kitchen” or “bath”.

[233] If FanPower not provided, defaults to 0.3 W/cfm based on the 2010 BAHSP.

[234] If StartHour not provided, defaults to 18 for kitchen fans and 7 for bath fans based on the 2010 BAHSP.

HPXML Whole House Fan¶

Each whole house fan that provides cooling load reduction is entered as a /HPXML/Building/BuildingDetails/Systems/MechanicalVentilation/VentilationFans/VentilationFan. If not entered, the simulation will not include whole house fans.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

UsedForSeasonalCoolingLoadReduction boolean true Yes Must be set to true

RatedFlowRate or TestedFlowRate or CalculatedFlowRate or DeliveredVentilation double cfm >= 0 No ConditionedFloorArea*2 Flow rate

FanPower double W >= 0 No See [234] Fan power

[235] If FanPower not provided, defaults to 0.1 W/cfm.

Note

The whole house fan is assumed to operate during hours of favorable outdoor conditions and will take priority over operable windows (natural ventilation).

HPXML Water Heating Systems¶

Each water heater is entered as a /HPXML/Building/BuildingDetails/Systems/WaterHeating/WaterHeatingSystem. If not entered, the simulation will not include water heating.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

IsSharedSystem boolean No false Whether it serves multiple dwelling units or shared laundry room

WaterHeaterType string See [235] Yes Type of water heater

Location string See [236] No See [237] Water heater location

FractionDHWLoadServed double frac 0 - 1 [238] Yes Fraction of hot water load served [239]

HotWaterTemperature double F > 0 No 125 Water heater setpoint

UsesDesuperheater boolean No false Presence of desuperheater?

NumberofUnitsServed integer > 0 See [240] Number of dwelling units served directly or indirectly

[236] WaterHeaterType choices are “storage water heater”, “instantaneous water heater”, “heat pump water heater”, “space-heating boiler with storage tank”, or “space-heating boiler with tankless coil”.

[237] Location choices are “living space”, “basement - unconditioned”, “basement - conditioned”, “attic - unvented”, “attic - vented”, “garage”, “crawlspace - unvented”, “crawlspace - vented”, “crawlspace - conditioned”, “other exterior”, “other housing unit”, “other heated space”, “other multifamily buffer space”, or “other non-freezing space”. See HPXML Locations for descriptions.

[238]
If Location not provided, defaults to the first present space type:

IECC zones 1-3, excluding 3A: “garage”, “living space”

IECC zones 3A, 4-8, unknown: “basement - conditioned”, “basement - unconditioned”, “living space”

[239] The sum of all FractionDHWLoadServed (across all WaterHeatingSystems) must equal to 1.

[240] FractionDHWLoadServed represents only the fraction of the hot water load associated with the hot water fixtures. Additional hot water load from clothes washers/dishwashers will be automatically assigned to the appropriate water heater(s).

[241] NumberofUnitsServed only required if IsSharedSystem is true, in which case it must be > 1.

Conventional Storage¶

If a conventional storage water heater is specified, additional information is entered in WaterHeatingSystem.

Element Type Units Constraints Required Default Notes

FuelType string See [241] Yes Fuel type

TankVolume double gal > 0 No See [242] Tank volume

HeatingCapacity double Btuh > 0 No See [243] Heating capacity

UniformEnergyFactor or EnergyFactor or YearInstalled double or integer frac or # < 1 or > 1600 Yes See [244] EnergyGuide label rated efficiency or Year installed

UsageBin or FirstHourRating string or double str or gal/hr See [245] or > 0 No See [246] EnergyGuide label usage bin/first hour rating

RecoveryEfficiency double frac 0 - 1 No See [247] Recovery efficiency

WaterHeaterInsulation/Jacket/JacketRValue double F-ft2-hr/Btu >= 0 No 0 R-value of additional tank insulation wrap

[242] FuelType choices are “natural gas”, “fuel oil”, “fuel oil 1”, “fuel oil 2”, “fuel oil 4”, “fuel oil 5/6”, “diesel”, “propane”, “kerosene”, “coal”, “coke”, “bituminous coal”, “anthracite coal”, “electricity”, “wood”, or “wood pellets”.

[243] If TankVolume not provided, defaults based on Table 8 in the 2014 BAHSP.

[244] If HeatingCapacity not provided, defaults based on Table 8 in the 2014 BAHSP.

[245] If UniformEnergyFactor and EnergyFactor not provided, defaults to EnergyFactor from the lookup table that can be found at HPXMLtoOpenStudio\resources\lu_water_heater_efficiency.csv based on YearInstalled.

[246] UsageBin choices are “very small”, “low”, “medium”, or “high”.

[247] UsageBin/FirstHourRating are only used for water heaters that use UniformEnergyFactor. If neither UsageBin nor FirstHourRating provided, UsageBin defaults to “medium”. If FirstHourRating provided and UsageBin not provided, UsageBin is determined based on the FirstHourRating value.

[248]
If RecoveryEfficiency not provided, defaults as follows based on a regression analysis of AHRI certified water heaters:

Electric: 0.98

Non-electric, EnergyFactor < 0.75: 0.252 * EnergyFactor + 0.608

Non-electric, EnergyFactor >= 0.75: 0.561 * EnergyFactor + 0.439

Tankless¶

If an instantaneous tankless water heater is specified, additional information is entered in WaterHeatingSystem.

Element Type Units Constraints Required Default Notes

FuelType string See [248] Yes Fuel type

PerformanceAdjustment double frac No See [249] Multiplier on efficiency, typically to account for cycling

UniformEnergyFactor or EnergyFactor double frac < 1 Yes EnergyGuide label rated efficiency

[249] FuelType choices are “natural gas”, “fuel oil”, “fuel oil 1”, “fuel oil 2”, “fuel oil 4”, “fuel oil 5/6”, “diesel”, “propane”, “kerosene”, “coal”, “coke”, “bituminous coal”, “anthracite coal”, “electricity”, “wood”, or “wood pellets”.

[250] If PerformanceAdjustment not provided, defaults to 0.94 (UEF) or 0.92 (EF) based on ANSI/RESNET/ICC 301-2019.

Heat Pump¶

If a heat pump water heater is specified, additional information is entered in WaterHeatingSystem.

Element Type Units Constraints Required Default Notes

FuelType string See [250] Yes Fuel type

TankVolume double gal > 0 Yes Tank volume

UniformEnergyFactor or EnergyFactor double frac > 1 Yes EnergyGuide label rated efficiency

UsageBin or FirstHourRating string or double str or gal/hr See [251] or > 0 No See [252] EnergyGuide label usage bin/first hour rating

WaterHeaterInsulation/Jacket/JacketRValue double F-ft2-hr/Btu >= 0 No 0 R-value of additional tank insulation wrap

[251] FuelType only choice is “electricity”.

[252] UsageBin choices are “very small”, “low”, “medium”, or “high”.

[253] UsageBin/FirstHourRating are only used for water heaters that use UniformEnergyFactor. If neither UsageBin nor FirstHourRating provided, UsageBin defaults to “medium”. If FirstHourRating provided and UsageBin not provided, UsageBin is determined based on the FirstHourRating value.

Combi Boiler w/ Storage¶

If a combination boiler w/ storage tank (sometimes referred to as an indirect water heater) is specified, additional information is entered in WaterHeatingSystem.

Element Type Units Constraints Required Default Notes

RelatedHVACSystem idref See [253] Yes ID of boiler

TankVolume double gal > 0 Yes Volume of the storage tank

WaterHeaterInsulation/Jacket/JacketRValue double F-ft2-hr/Btu >= 0 No 0 R-value of additional storage tank insulation wrap

StandbyLoss double F/hr > 0 No See [254] Storage tank standby losses

[254] RelatedHVACSystem must reference a HeatingSystem of type Boiler.

[255] If StandbyLoss not provided, defaults based on a regression analysis of AHRI Directory of Certified Product Performance.

Combi Boiler w/ Tankless Coil¶

If a combination boiler w/ tankless coil is specified, additional information is entered in WaterHeatingSystem.

Element Type Units Constraints Required Default Notes

RelatedHVACSystem idref See [255] Yes ID of boiler

[256] RelatedHVACSystem must reference a HeatingSystem (Boiler).

Desuperheater¶

If the water heater uses a desuperheater, additional information is entered in WaterHeatingSystem.

Element Type Units Constraints Required Default Notes

RelatedHVACSystem idref See [256] Yes ID of heat pump or air conditioner

[257] RelatedHVACSystem must reference a HeatPump (air-to-air, mini-split, or ground-to-air) or CoolingSystem (central air conditioner or mini-split).

HPXML Hot Water Distribution¶

If any water heating systems are provided, a single hot water distribution system is entered as a /HPXML/Building/BuildingDetails/Systems/WaterHeating/HotWaterDistribution.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

SystemType element 1 [257] Yes Type of in-unit distribution system serving the dwelling unit

PipeInsulation/PipeRValue double F-ft2-hr/Btu >= 0 No 0.0 Pipe insulation R-value

DrainWaterHeatRecovery element 0 - 1 No <none> Presence of drain water heat recovery device

extension/SharedRecirculation element 0 - 1 [258] No <none> Presence of shared recirculation system serving multiple dwelling units

[258] SystemType child element choices are Standard and Recirculation.

[259] If SharedRecirculation is provided, SystemType must be Standard. This is because a stacked recirculation system (i.e., shared recirculation loop plus an additional in-unit recirculation system) is more likely to indicate input errors than reflect an actual real-world scenario.

Note

In attached/multifamily buildings, only the hot water distribution system serving the dwelling unit should be defined. The hot water distribution associated with, e.g., a shared laundry room should not be defined.

Standard¶

If the in-unit distribution system is specified as standard, additional information is entered in SystemType/Standard.

Element Type Units Constraints Required Default Notes

PipingLength double ft > 0 No See [259] Length of piping [260]

[260]

If PipingLength not provided, calculated using the following equation from ANSI/RESNET/ICC 301-2019:

PipeL = 2.0 * (CFA / NCfl)^0.5 + 10.0 * NCfl + 5.0 * Bsmnt

where

CFA = conditioned floor area [ft2],

NCfl = number of conditioned floor levels number of conditioned floor levels in the residence including conditioned basements,

Bsmnt = presence (1.0) or absence (0.0) of an unconditioned basement in the residence.

[261] PipingLength is the length of hot water piping from the hot water heater (or from a shared recirculation loop serving multiple dwelling units) to the farthest hot water fixture, measured longitudinally from plans, assuming the hot water piping does not run diagonally, plus 10 feet of piping for each floor level, plus 5 feet of piping for unconditioned basements (if any).

Recirculation¶

If the in-unit distribution system is specified as recirculation, additional information is entered in SystemType/Recirculation.

Element Type Units Constraints Required Default Notes

ControlType string See [261] Yes Recirculation control type

RecirculationPipingLoopLength double ft > 0 No See [262] Recirculation piping loop length [263]

BranchPipingLoopLength double ft > 0 No 10 Branch piping loop length [264]

PumpPower double W >= 0 No 50 [265] Recirculation pump power

[262] ControlType choices are “manual demand control”, “presence sensor demand control”, “temperature”, “timer”, or “no control”.

[263]

If RecirculationPipingLoopLength not provided, calculated using the following equation from ANSI/RESNET/ICC 301-2019:

RecircPipeL = 2.0 * (2.0 * (CFA / NCfl)^0.5 + 10.0 * NCfl + 5.0 * Bsmnt) - 20.0

where

CFA = conditioned floor area [ft2],

NCfl = number of conditioned floor levels number of conditioned floor levels in the residence including conditioned basements,

Bsmnt = presence (1.0) or absence (0.0) of an unconditioned basement in the residence.

[264] RecirculationPipingLoopLength is the recirculation loop length including both supply and return sides, measured longitudinally from plans, assuming the hot water piping does not run diagonally, plus 20 feet of piping for each floor level greater than one plus 10 feet of piping for unconditioned basements.

[265] BranchPipingLoopLength is the length of the branch hot water piping from the recirculation loop to the farthest hot water fixture from the recirculation loop, measured longitudinally from plans, assuming the branch hot water piping does not run diagonally.

[266] PumpPower default based on ANSI/RESNET/ICC 301-2019.

Shared Recirculation¶

If a shared recirculation system is specified, additional information is entered in extension/SharedRecirculation.

Element Type Units Constraints Required Default Notes

NumberofUnitsServed integer > 1 Yes Number of dwelling units served

PumpPower double W >= 0 No 220 [266] Shared recirculation pump power

ControlType string See [267] Yes Shared recirculation control type

[267] PumpPower default based on ANSI/RESNET/ICC 301-2019.

[268] ControlType choices are “manual demand control”, “presence sensor demand control”, “timer”, or “no control”.

Drain Water Heat Recovery¶

If a drain water heat recovery (DWHR) device is specified, additional information is entered in DrainWaterHeatRecovery.

Element Type Units Constraints Required Default Notes

FacilitiesConnected string See [268] Yes Specifies which facilities are connected

EqualFlow boolean Yes Specifies how the DHWR is configured [269]

Efficiency double frac 0 - 1 Yes Efficiency according to CSA 55.1

[269] FacilitiesConnected choices are “one” or “all”. Use “one” if there are multiple showers and only one of them is connected to the DWHR. Use “all” if there is one shower and it’s connected to the DWHR or there are two or more showers connected to the DWHR.

[270] EqualFlow should be true if the DWHR supplies pre-heated water to both the fixture cold water piping and the hot water heater potable supply piping.

HPXML Water Fixtures¶

Each water fixture is entered as a /HPXML/Building/BuildingDetails/Systems/WaterHeating/WaterFixture.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

WaterFixtureType string See [270] Yes Type of water fixture

LowFlow boolean Yes Whether the fixture is considered low-flow [271]

[271] WaterFixtureType choices are “shower head” or “faucet”.

[272] LowFlow should be true if the fixture’s flow rate (gpm) is <= 2.0.

Additional information can be entered in /HPXML/Building/BuildingDetails/Systems/WaterHeating/.

Element Type Units Constraints Required Default Notes

extension/WaterFixturesUsageMultiplier double >= 0 No 1.0 Multiplier on hot water usage

extension/WaterFixturesWeekdayScheduleFractions array No See [272] 24 comma-separated weekday fractions

extension/WaterFixturesWeekendScheduleFractions array No 24 comma-separated weekend fractions

extension/WaterFixturesMonthlyScheduleMultipliers array No See [273] 12 comma-separated monthly multipliers

[273] If WaterFixturesWeekdayScheduleFractions or WaterFixturesWeekendScheduleFractions not provided (and Detailed Schedule Inputs not used), default values from Figures 9-11 of the 2010 BAHSP are used: “0.012, 0.006, 0.004, 0.005, 0.010, 0.034, 0.078, 0.087, 0.080, 0.067, 0.056, 0.047, 0.040, 0.035, 0.033, 0.031, 0.039, 0.051, 0.060, 0.060, 0.055, 0.048, 0.038, 0.026”.

[274] If WaterFixturesMonthlyScheduleMultipliers not provided (and Detailed Schedule Inputs not used), default values are used: “1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0”.

HPXML Solar Thermal¶

A single solar hot water system can be entered as a /HPXML/Building/BuildingDetails/Systems/SolarThermal/SolarThermalSystem. If not entered, the simulation will not include solar hot water.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

SystemType string See [274] Yes Type of solar thermal system

[275] SystemType only choice is “hot water”.

Solar hot water systems can be described with either simple or detailed inputs.

Simple Inputs¶

To define a simple solar hot water system, additional information is entered in SolarThermalSystem.

Element Type Units Constraints Required Default Notes

SolarFraction double frac 0 - 1 Yes Solar fraction [275]

ConnectedTo idref See [276] No [277] <none> Connected water heater

[276] Portion of total conventional hot water heating load (delivered energy plus tank standby losses). Can be obtained from Directory of SRCC OG-300 Solar Water Heating System Ratings or NREL’s System Advisor Model or equivalent.

[277] ConnectedTo must reference a WaterHeatingSystem. The referenced water heater cannot be a space-heating boiler nor attached to a desuperheater.

[278] If ConnectedTo not provided, solar fraction will apply to all water heaters in the building.

Detailed Inputs¶

To define a detailed solar hot water system, additional information is entered in SolarThermalSystem.

Element Type Units Constraints Required Default Notes

CollectorArea double ft2 > 0 Yes Area

CollectorLoopType string See [278] Yes Loop type

CollectorType string See [279] Yes System type

CollectorAzimuth or CollectorOrientation integer or string deg or direction 0 - 359 or See [280] Yes Direction panels face (clockwise from North)

CollectorTilt double deg 0 - 90 Yes Tilt relative to horizontal

CollectorRatedOpticalEfficiency double frac 0 - 1 Yes Rated optical efficiency [281]

CollectorRatedThermalLosses double Btu/hr-ft2-R > 0 Yes Rated thermal losses [282]

StorageVolume double gal > 0 No See [283] Hot water storage volume

ConnectedTo idref See [284] Yes Connected water heater

[279] CollectorLoopType choices are “liquid indirect”, “liquid direct”, or “passive thermosyphon”.

[280] CollectorType choices are “single glazing black”, “double glazing black”, “evacuated tube”, or “integrated collector storage”.

[281] CollectorOrientation choices are “northeast”, “east”, “southeast”, “south”, “southwest”, “west”, “northwest”, or “north”

[282] CollectorRatedOpticalEfficiency is FRTA (y-intercept) from the Directory of SRCC OG-100 Certified Solar Collector Ratings.

[283] CollectorRatedThermalLosses is FRUL (slope) from the Directory of SRCC OG-100 Certified Solar Collector Ratings.

[284] If StorageVolume not provided, calculated as 1.5 gal/ft2 * CollectorArea.

[285] ConnectedTo must reference a WaterHeatingSystem that is not of type space-heating boiler nor connected to a desuperheater.

HPXML Photovoltaics¶

Each solar electric photovoltaic (PV) system is entered as a /HPXML/Building/BuildingDetails/Systems/Photovoltaics/PVSystem. If not entered, the simulation will not include photovoltaics.

Many of the inputs are adopted from the PVWatts model.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

IsSharedSystem boolean No false Whether it serves multiple dwelling units

Location string See [285] No roof Mounting location

ModuleType string See [286] No standard Type of module

Tracking string See [287] No fixed Type of tracking

ArrayAzimuth or ArrayOrientation integer or string deg or direction 0 - 359 or See [288] Yes Direction panels face (clockwise from North)

ArrayTilt double deg 0 - 90 Yes Tilt relative to horizontal

MaxPowerOutput double W >= 0 Yes Peak power

InverterEfficiency double frac 0 - 1 [289] No 0.96 Inverter efficiency

SystemLossesFraction or YearModulesManufactured double or integer frac or # 0 - 1 or > 1600 No 0.14 System losses [290]

extension/NumberofBedroomsServed integer > 1 See [291] Number of bedrooms served

[286] Location choices are “ground” or “roof” mounted.

[287] ModuleType choices are “standard”, “premium”, or “thin film”.

[288] Tracking choices are “fixed”, “1-axis”, “1-axis backtracked”, or “2-axis”.

[289] ArrayOrientation choices are “northeast”, “east”, “southeast”, “south”, “southwest”, “west”, “northwest”, or “north”

[290] For homes with multiple PV arrays, all InverterEfficiency elements must have the same value.

[291] System losses due to soiling, shading, snow, mismatch, wiring, degradation, etc. If YearModulesManufactured provided but not SystemLossesFraction, system losses calculated as: SystemLossesFraction = 1.0 - (1.0 - 0.14) * (1.0 - (1.0 - 0.995^(CurrentYear - YearModulesManufactured))).

[292] NumberofBedroomsServed only required if IsSharedSystem is true, in which case it must be > NumberofBedrooms. PV generation will be apportioned to the dwelling unit using its number of bedrooms divided by the total number of bedrooms served by the PV system.

HPXML Batteries¶

A single battery can be entered as a /HPXML/Building/BuildingDetails/Systems/Batteries/Battery. If not entered, the simulation will not include batteries.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

Location string See [292] No outside Location

BatteryType string See [293] Yes Battery type

NominalCapacity[Units="kWh" or Units="Ah"]/Value double kWh or Ah >= 0 No See [294] Nominal (not usable) capacity

RatedPowerOutput double W >= 0 No See [295] Rated power output

NominalVoltage double V >= 0 No 50 Nominal voltage

extension/LifetimeModel string See [296] No None Lifetime model [297]

[293] Location choices are “living space”, “basement - conditioned”, “basement - unconditioned”, “crawlspace - vented”, “crawlspace - unvented”, “crawlspace - conditioned”, “attic - vented”, “attic - unvented”, “garage”, or “outside”.

[294] BatteryType choices are “Li-ion”.

[295] NominalCapacity is defaulted to 10 kWh if RatedPowerOutput is not specified; otherwise it is calculated as (RatedPowerOutput / 1000) / 0.5.

[296] RatedPowerOutput is defaulted to 5000 W if NominalCapacity is not specified; otherwise it is calculated as NominalCapacity * 1000 * 0.5.

[297] LifetimeModel choices are “None” or “KandlerSmith”.

[298] See the “Lifetime Model” EnergyPlus documentation for more information.

HPXML Generators¶

Each generator that provides on-site power is entered as a /HPXML/Building/BuildingDetails/Systems/extension/Generators/Generator. If not entered, the simulation will not include generators.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

IsSharedSystem boolean No false Whether it serves multiple dwelling units

FuelType string See [298] Yes Fuel type

AnnualConsumptionkBtu double kBtu/yr > 0 Yes Annual fuel consumed

AnnualOutputkWh double kWh/yr > 0 [299] Yes Annual electricity produced

NumberofBedroomsServed integer > 1 See [300] Number of bedrooms served

[299] FuelType choices are “natural gas”, “fuel oil”, “fuel oil 1”, “fuel oil 2”, “fuel oil 4”, “fuel oil 5/6”, “diesel”, “propane”, “kerosene”, “coal”, “coke”, “bituminous coal”, “anthracite coal”, “wood”, or “wood pellets”.

[300] AnnualOutputkWh must also be < AnnualConsumptionkBtu*3.412 (i.e., the generator must consume more energy than it produces).

[301] NumberofBedroomsServed only required if IsSharedSystem is true, in which case it must be > NumberofBedrooms. Annual consumption and annual production will be apportioned to the dwelling unit using its number of bedrooms divided by the total number of bedrooms served by the generator.

Note

Generators will be modeled as operating continuously (24/7).

HPXML Appliances¶

Appliances entered in /HPXML/Building/BuildingDetails/Appliances.

HPXML Clothes Washer¶

A single clothes washer can be entered as a /HPXML/Building/BuildingDetails/Appliances/ClothesWasher. If not entered, the simulation will not include a clothes washer.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

IsSharedAppliance boolean No false Whether it serves multiple dwelling units [301]

Location string See [302] No living space Location

IntegratedModifiedEnergyFactor or ModifiedEnergyFactor double ft3/kWh/cyc > 0 No See [303] EnergyGuide label efficiency [304]

AttachedToWaterHeatingSystem idref See [305] See [306] ID of attached water heater

extension/UsageMultiplier double >= 0 No 1.0 Multiplier on energy & hot water usage

extension/WeekdayScheduleFractions array No See [307] 24 comma-separated weekday fractions

extension/WeekendScheduleFractions array No 24 comma-separated weekend fractions

extension/MonthlyScheduleMultipliers array No See [308] 12 comma-separated monthly multipliers

[302] For example, a clothes washer in a shared laundry room of a MF building.

[303] Location choices are “living space”, “basement - conditioned”, “basement - unconditioned”, “garage”, “other housing unit”, “other heated space”, “other multifamily buffer space”, or “other non-freezing space”. See HPXML Locations for descriptions.

[304] If neither IntegratedModifiedEnergyFactor nor ModifiedEnergyFactor provided, the following default values representing a standard clothes washer from 2006 will be used: IntegratedModifiedEnergyFactor = 1.0, RatedAnnualkWh = 400, LabelElectricRate = 0.12, LabelGasRate = 1.09, LabelAnnualGasCost = 27.0, LabelUsage = 6, Capacity = 3.0.

[305] If ModifiedEnergyFactor (MEF) provided instead of IntegratedModifiedEnergyFactor (IMEF), it will be converted using the Interpretation on ANSI/RESNET 301-2014 Clothes Washer IMEF: IMEF = (MEF - 0.503) / 0.95.

[306] AttachedToWaterHeatingSystem must reference a WaterHeatingSystem.

[307] AttachedToWaterHeatingSystem only required if IsSharedAppliance is true.

[308] If WeekdayScheduleFractions or WeekendScheduleFractions not provided (and Detailed Schedule Inputs not used), default values from Figure 17 of the 2010 BAHSP are used: “0.009, 0.007, 0.004, 0.004, 0.007, 0.011, 0.022, 0.049, 0.073, 0.086, 0.084, 0.075, 0.067, 0.060, 0.049, 0.052, 0.050, 0.049, 0.049, 0.049, 0.049, 0.047, 0.032, 0.017”.

[309] If MonthlyScheduleMultipliers not provided (and Detailed Schedule Inputs not used), default values from Figure 24 of the 2010 BAHSP are used: “1.011, 1.002, 1.022, 1.020, 1.022, 0.996, 0.999, 0.999, 0.996, 0.964, 0.959, 1.011”.

If IntegratedModifiedEnergyFactor or ModifiedEnergyFactor is provided, a complete set of EnergyGuide label information is entered in ClothesWasher.

Element Type Units Constraints Required Default Notes

RatedAnnualkWh double kWh/yr > 0 Yes EnergyGuide label annual consumption

LabelElectricRate double $/kWh > 0 Yes EnergyGuide label electricity rate

LabelGasRate double $/therm > 0 Yes EnergyGuide label natural gas rate

LabelAnnualGasCost double $ > 0 Yes EnergyGuide label annual gas cost

LabelUsage double cyc/wk > 0 Yes EnergyGuide label number of cycles

Capacity double ft3 > 0 Yes Clothes dryer volume

Clothes washer energy use and hot water use is calculated per the Energy Rating Rated Home in ANSI/RESNET/ICC 301-2019 Addendum A.

HPXML Clothes Dryer¶

A single clothes dryer can be entered as a /HPXML/Building/BuildingDetails/Appliances/ClothesDryer. If not entered, the simulation will not include a clothes dryer.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

IsSharedAppliance boolean No false Whether it serves multiple dwelling units [309]

Location string See [310] No living space Location

FuelType string See [311] Yes Fuel type

CombinedEnergyFactor or EnergyFactor double lb/kWh > 0 No See [312] EnergyGuide label efficiency [313]

Vented boolean No true Whether dryer is vented

VentedFlowRate double cfm >= 0 No 100 [314] Exhaust flow rate during operation

extension/UsageMultiplier double >= 0 No 1.0 Multiplier on energy use

extension/WeekdayScheduleFractions array No See [315] 24 comma-separated weekday fractions

extension/WeekendScheduleFractions array No 24 comma-separated weekend fractions

extension/MonthlyScheduleMultipliers array No See [316] 12 comma-separated monthly multipliers

[310] For example, a clothes dryer in a shared laundry room of a MF building.

[311] Location choices are “living space”, “basement - conditioned”, “basement - unconditioned”, “garage”, “other housing unit”, “other heated space”, “other multifamily buffer space”, or “other non-freezing space”. See HPXML Locations for descriptions.

[312] FuelType choices are “natural gas”, “fuel oil”, “fuel oil 1”, “fuel oil 2”, “fuel oil 4”, “fuel oil 5/6”, “diesel”, “propane”, “kerosene”, “coal”, “coke”, “bituminous coal”, “anthracite coal”, “electricity”, “wood”, or “wood pellets”.

[313] If neither CombinedEnergyFactor nor EnergyFactor provided, the following default values representing a standard clothes dryer from 2006 will be used: CombinedEnergyFactor = 3.01.

[314] If EnergyFactor (EF) provided instead of CombinedEnergyFactor (CEF), it will be converted using the following equation based on the Interpretation on ANSI/RESNET/ICC 301-2014 Clothes Dryer CEF: CEF = EF / 1.15.

[315] VentedFlowRate default based on the 2010 BAHSP.

[316] If WeekdayScheduleFractions or WeekendScheduleFractions not provided (and Detailed Schedule Inputs not used), default values from Figure 18 of the 2010 BAHSP are used: “0.010, 0.006, 0.004, 0.002, 0.004, 0.006, 0.016, 0.032, 0.048, 0.068, 0.078, 0.081, 0.074, 0.067, 0.057, 0.061, 0.055, 0.054, 0.051, 0.051, 0.052, 0.054, 0.044, 0.024”.

[317] If MonthlyScheduleMultipliers not provided (and Detailed Schedule Inputs not used), default values are used: “1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0”.

Clothes dryer energy use is calculated per the Energy Rating Rated Home in ANSI/RESNET/ICC 301-2019 Addendum A.

HPXML Dishwasher¶

A single dishwasher can be entered as a /HPXML/Building/BuildingDetails/Appliances/Dishwasher. If not entered, the simulation will not include a dishwasher.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

IsSharedAppliance boolean No false Whether it serves multiple dwelling units [317]

Location string See [318] No living space Location

RatedAnnualkWh or EnergyFactor double kWh/yr or # > 0 No See [319] EnergyGuide label consumption/efficiency [320]

AttachedToWaterHeatingSystem idref See [321] See [322] ID of attached water heater

extension/UsageMultiplier double >= 0 No 1.0 Multiplier on energy & hot water usage

extension/WeekdayScheduleFractions array No See [323] 24 comma-separated weekday fractions

extension/WeekendScheduleFractions array No 24 comma-separated weekend fractions

extension/MonthlyScheduleMultipliers array No See [324] 12 comma-separated monthly multipliers

[318] For example, a dishwasher in a shared mechanical room of a MF building.

[319] Location choices are “living space”, “basement - conditioned”, “basement - unconditioned”, “garage”, “other housing unit”, “other heated space”, “other multifamily buffer space”, or “other non-freezing space”. See HPXML Locations for descriptions.

[320] If neither RatedAnnualkWh nor EnergyFactor provided, the following default values representing a standard dishwasher from 2006 will be used: RatedAnnualkWh = 467, LabelElectricRate = 0.12, LabelGasRate = 1.09, LabelAnnualGasCost = 33.12, LabelUsage = 4, PlaceSettingCapacity = 12.

[321] If EnergyFactor (EF) provided instead of RatedAnnualkWh, it will be converted using the following equation based on ANSI/RESNET/ICC 301-2014: RatedAnnualkWh = 215.0 / EF.

[322] AttachedToWaterHeatingSystem must reference a WaterHeatingSystem.

[323] AttachedToWaterHeatingSystem only required if IsSharedAppliance is true.

[324] If WeekdayScheduleFractions or WeekendScheduleFractions not provided (and Detailed Schedule Inputs not used), default values from Figure 21 of the 2010 BAHSP are used: “0.015, 0.007, 0.005, 0.003, 0.003, 0.010, 0.020, 0.031, 0.058, 0.065, 0.056, 0.048, 0.041, 0.046, 0.036, 0.038, 0.038, 0.049, 0.087, 0.111, 0.090, 0.067, 0.044, 0.031”.

[325] If MonthlyScheduleMultipliers not provided (and Detailed Schedule Inputs not used), default values from Figure 24 of the 2010 BAHSP are used: “1.097, 1.097, 0.991, 0.987, 0.991, 0.890, 0.896, 0.896, 0.890, 1.085, 1.085, 1.097”.

If the RatedAnnualkWh or EnergyFactor is provided, a complete set of EnergyGuide label information is entered in Dishwasher.

Element Type Units Constraints Required Default Notes

LabelElectricRate double $/kWh > 0 Yes EnergyGuide label electricity rate

LabelGasRate double $/therm > 0 Yes EnergyGuide label natural gas rate

LabelAnnualGasCost double $ > 0 Yes EnergyGuide label annual gas cost

LabelUsage double cyc/wk > 0 Yes EnergyGuide label number of cycles

PlaceSettingCapacity integer # > 0 Yes Number of place settings

Dishwasher energy use and hot water use is calculated per the Energy Rating Rated Home in ANSI/RESNET/ICC 301-2019 Addendum A.

HPXML Refrigerators¶

Each refrigerator can be entered as a /HPXML/Building/BuildingDetails/Appliances/Refrigerator. If not entered, the simulation will not include a refrigerator.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

Location string See [325] No See [326] Location

RatedAnnualkWh double kWh/yr > 0 No See [327] Annual consumption

PrimaryIndicator boolean See [328] Primary refrigerator?

extension/UsageMultiplier double >= 0 No 1.0 Multiplier on energy use

extension/WeekdayScheduleFractions array No See [329] 24 comma-separated weekday fractions

extension/WeekendScheduleFractions array No 24 comma-separated weekend fractions

extension/MonthlyScheduleMultipliers array No See [330] 12 comma-separated monthly multipliers

[326] Location choices are “living space”, “basement - conditioned”, “basement - unconditioned”, “garage”, “other housing unit”, “other heated space”, “other multifamily buffer space”, or “other non-freezing space”. See HPXML Locations for descriptions.

[327] If Location not provided and is the primary refrigerator, defaults to “living space”. If Location not provided and is a secondary refrigerator, defaults to the first present space type: “garage”, “basement - unconditioned”, “basement - conditioned”, or “living space”.

[328] If RatedAnnualkWh not provided, it will be defaulted to represent a standard refrigerator from 2006 using the following equation based on ANSI/RESNET/ICC 301-2019: RatedAnnualkWh = 637.0 + 18.0 * NumberofBedrooms.

[329] If multiple refrigerators are specified, there must be exactly one refrigerator described with PrimaryIndicator=true.

[330] If WeekdayScheduleFractions or WeekendScheduleFractions not provided (and Detailed Schedule Inputs not used), default values from Figure 16 of the 2010 BAHSP are used: “0.040, 0.039, 0.038, 0.037, 0.036, 0.036, 0.038, 0.040, 0.041, 0.041, 0.040, 0.040, 0.042, 0.042, 0.042, 0.041, 0.044, 0.048, 0.050, 0.048, 0.047, 0.046, 0.044, 0.041”.

[331] If MonthlyScheduleMultipliers not provided (and Detailed Schedule Inputs not used), default values from Figure 24 of the 2010 BAHSP are used: “0.837, 0.835, 1.084, 1.084, 1.084, 1.096, 1.096, 1.096, 1.096, 0.931, 0.925, 0.837”.

HPXML Freezers¶

Each standalone freezer can be entered as a /HPXML/Building/BuildingDetails/Appliances/Freezer. If not entered, the simulation will not include a standalone freezer.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

Location string See [331] No See [332] Location

RatedAnnualkWh double kWh/yr > 0 No 319.8 [333] Annual consumption

extension/UsageMultiplier double >= 0 No 1.0 Multiplier on energy use

extension/WeekdayScheduleFractions array No See [334] 24 comma-separated weekday fractions

extension/WeekendScheduleFractions array No 24 comma-separated weekend fractions

extension/MonthlyScheduleMultipliers array No See [335] 12 comma-separated monthly multipliers

[332] Location choices are “living space”, “basement - conditioned”, “basement - unconditioned”, “garage”, “other housing unit”, “other heated space”, “other multifamily buffer space”, or “other non-freezing space”. See HPXML Locations for descriptions.

[333] If Location not provided, defaults to “garage” if present, otherwise “basement - unconditioned” if present, otherwise “basement - conditioned” if present, otherwise “living space”.

[334] RatedAnnualkWh default based on the 2010 BAHSP.

[335] If WeekdayScheduleFractions or WeekendScheduleFractions not provided (and Detailed Schedule Inputs not used), default values from Figure 16 of the 2010 BAHSP are used: “0.040, 0.039, 0.038, 0.037, 0.036, 0.036, 0.038, 0.040, 0.041, 0.041, 0.040, 0.040, 0.042, 0.042, 0.042, 0.041, 0.044, 0.048, 0.050, 0.048, 0.047, 0.046, 0.044, 0.041”.

[336] If MonthlyScheduleMultipliers not provided (and Detailed Schedule Inputs not used), default values from Figure 24 of the 2010 BAHSP are used: “0.837, 0.835, 1.084, 1.084, 1.084, 1.096, 1.096, 1.096, 1.096, 0.931, 0.925, 0.837”.

HPXML Dehumidifier¶

Each dehumidifier can be entered as a /HPXML/Building/BuildingDetails/Appliances/Dehumidifier. If not entered, the simulation will not include a dehumidifier.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

Type string See [336] Yes Type of dehumidifier

Location string See [337] Yes Location of dehumidifier

Capacity double pints/day > 0 Yes Dehumidification capacity

IntegratedEnergyFactor or EnergyFactor double liters/kWh > 0 Yes Rated efficiency

DehumidistatSetpoint double frac 0 - 1 [338] Yes Relative humidity setpoint

FractionDehumidificationLoadServed double frac 0 - 1 [339] Yes Fraction of dehumidification load served

[337] Type choices are “portable” or “whole-home”.

[338] Location only choice is “living space”.

[339] If multiple dehumidifiers are entered, they must all have the same setpoint or an error will be generated.

[340] The sum of all FractionDehumidificationLoadServed (across all Dehumidifiers) must be less than or equal to 1.

Note

Dehumidifiers are currently modeled as located within conditioned space; the model is not suited for a dehumidifier in, e.g., a wet unconditioned basement or crawlspace. Therefore the dehumidifier Location is currently restricted to “living space”.

HPXML Cooking Range/Oven¶

A single cooking range can be entered as a /HPXML/Building/BuildingDetails/Appliances/CookingRange. If not entered, the simulation will not include a cooking range/oven.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

Location string See [340] No living space Location

FuelType string See [341] Yes Fuel type

IsInduction boolean No false Induction range?

extension/UsageMultiplier double >= 0 No 1.0 Multiplier on energy use

extension/WeekdayScheduleFractions array No See [342] 24 comma-separated weekday fractions

extension/WeekendScheduleFractions array No 24 comma-separated weekend fractions

extension/MonthlyScheduleMultipliers array No See [343] 12 comma-separated monthly multipliers

[341] Location choices are “living space”, “basement - conditioned”, “basement - unconditioned”, “garage”, “other housing unit”, “other heated space”, “other multifamily buffer space”, or “other non-freezing space”. See HPXML Locations for descriptions.

[342] FuelType choices are “natural gas”, “fuel oil”, “fuel oil 1”, “fuel oil 2”, “fuel oil 4”, “fuel oil 5/6”, “diesel”, “propane”, “kerosene”, “coal”, “coke”, “bituminous coal”, “anthracite coal”, “electricity”, “wood”, or “wood pellets”.

[343] If WeekdayScheduleFractions or WeekendScheduleFractions not provided (and Detailed Schedule Inputs not used), default values from Figure 22 of the 2010 BAHSP are used: “0.007, 0.007, 0.004, 0.004, 0.007, 0.011, 0.025, 0.042, 0.046, 0.048, 0.042, 0.050, 0.057, 0.046, 0.057, 0.044, 0.092, 0.150, 0.117, 0.060, 0.035, 0.025, 0.016, 0.011”.

[344] If MonthlyScheduleMultipliers not provided (and Detailed Schedule Inputs not used), default values from Figure 24 of the 2010 BAHSP are used: “1.097, 1.097, 0.991, 0.987, 0.991, 0.890, 0.896, 0.896, 0.890, 1.085, 1.085, 1.097”.

If a cooking range is specified, a single oven is also entered as a /HPXML/Building/BuildingDetails/Appliances/Oven.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

IsConvection boolean No false Convection oven?

Cooking range/oven energy use is calculated per the Energy Rating Rated Home in ANSI/RESNET/ICC 301-2019.

HPXML Lighting & Ceiling Fans¶

Lighting and ceiling fans are entered in /HPXML/Building/BuildingDetails/Lighting.

HPXML Lighting¶

Nine /HPXML/Building/BuildingDetails/Lighting/LightingGroup elements must be provided, each of which is the combination of:

LightingType: ‘LightEmittingDiode’, ‘CompactFluorescent’, and ‘FluorescentTube’
Location: ‘interior’, ‘garage’, and ‘exterior’

Information is entered in each LightingGroup.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

LightingType element 1 [344] Yes Lighting type

Location string See [345] Yes See [346]

FractionofUnitsInLocation double frac 0 - 1 [347] Yes Fraction of light fixtures in the location with the specified lighting type

[345] LightingType child element choices are LightEmittingDiode, CompactFluorescent, or FluorescentTube.

[346] Location choices are “interior”, “garage”, or “exterior”.

[347] Garage lighting is ignored if the building has no garage specified elsewhere.

[348] The sum of FractionofUnitsInLocation for a given Location (e.g., interior) must be less than or equal to 1. If the fractions sum to less than 1, the remainder is assumed to be incandescent lighting.

Additional information is entered in Lighting.

Element Type Units Constraints Required Default Notes

extension/InteriorUsageMultiplier double >= 0 No 1.0 Multiplier on interior lighting use

extension/GarageUsageMultiplier double >= 0 No 1.0 Multiplier on garage lighting use

extension/ExteriorUsageMultiplier double >= 0 No 1.0 Multiplier on exterior lighting use

extension/InteriorWeekdayScheduleFractions array No See [348] 24 comma-separated interior weekday fractions

extension/InteriorWeekendScheduleFractions array No 24 comma-separated interior weekend fractions

extension/InteriorMonthlyScheduleMultipliers array No 12 comma-separated interior monthly multipliers

extension/GarageWeekdayScheduleFractions array No See [349] 24 comma-separated garage weekday fractions

extension/GarageWeekendScheduleFractions array No 24 comma-separated garage weekend fractions

extension/GarageMonthlyScheduleMultipliers array No 12 comma-separated garage monthly multipliers

extension/ExteriorWeekdayScheduleFractions array No See [350] 24 comma-separated exterior weekday fractions

extension/ExteriorWeekendScheduleFractions array No 24 comma-separated exterior weekend fractions

extension/ExteriorMonthlyScheduleMultipliers array No 12 comma-separated exterior monthly multipliers

extension/ExteriorHolidayLighting element 0 - 1 No <none> Presence of additional holiday lighting?

[349] If interior schedule values not provided (and Detailed Schedule Inputs not used), they will be calculated using Lighting Calculation Option 2 (location-dependent lighting profile) of the 2010 BAHSP.

[350] If garage schedule values not provided (and Detailed Schedule Inputs not used), they will be defaulted using Appendix C Table 8 of the Title 24 2016 Res. ACM Manual.

[351] If exterior schedule values not provided (and Detailed Schedule Inputs not used), they will be defaulted using Appendix C Table 8 of the Title 24 2016 Res. ACM Manual.

If exterior holiday lighting is specified, additional information is entered in extension/ExteriorHolidayLighting.

Element Type Units Constraints Required Default Notes

Load[Units="kWh/day"]/Value double kWh/day >= 0 No See [351] Holiday lighting energy use per day

PeriodBeginMonth integer 1 - 12 No 11 (November) Holiday lighting start date

PeriodBeginDayOfMonth integer 1 - 31 No 24 Holiday lighting start date

PeriodEndMonth integer 1 - 12 No 1 (January) Holiday lighting end date

PeriodEndDayOfMonth integer 1 - 31 No 6 Holiday lighting end date

WeekdayScheduleFractions array No See [352] 24 comma-separated holiday weekday fractions

WeekendScheduleFractions array No 24 comma-separated holiday weekend fractions

[352] If Value not provided, defaults to 1.1 for single-family detached and 0.55 for others.

[353] If WeekdayScheduleFractions not provided (and Detailed Schedule Inputs not used), defaults to “0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0.008, 0.098, 0.168, 0.194, 0.284, 0.192, 0.037, 0.019”.

Interior, exterior, and garage lighting energy use is calculated per the Energy Rating Rated Home in ANSI/RESNET/ICC 301-2019.

HPXML Ceiling Fans¶

Each ceiling fan is entered as a /HPXML/Building/BuildingDetails/Lighting/CeilingFan. If not entered, the simulation will not include a ceiling fan.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

Airflow[FanSpeed="medium"]/Efficiency double cfm/W > 0 No See [353] Efficiency at medium speed

Quantity integer > 0 No See [354] Number of similar ceiling fans

extension/WeekdayScheduleFractions array No See [355] 24 comma-separated weekday fractions

extension/WeekendScheduleFractions array No 24 comma-separated weekend fractions

extension/MonthlyScheduleMultipliers array No See [356] 12 comma-separated monthly multipliers

[354] If Efficiency not provided, defaults to 3000 / 42.6 based on ANSI/RESNET/ICC 301-2019.

[355] If Quantity not provided, defaults to NumberofBedrooms + 1 based on ANSI/RESNET/ICC 301-2019.

[356] If WeekdayScheduleFractions or WeekendScheduleFractions not provided (and Detailed Schedule Inputs not used), default values from Figure 23 of the 2010 BAHSP are used: “0.057, 0.057, 0.057, 0.057, 0.057, 0.057, 0.057, 0.024, 0.024, 0.024, 0.024, 0.024, 0.024, 0.024, 0.024, 0.024, 0.024, 0.024, 0.057, 0.057, 0.057, 0.057, 0.057, 0.057”.

[357] If MonthlyScheduleMultipliers not provided (and Detailed Schedule Inputs not used), defaults based on monthly average outdoor temperatures per ANSI/RESNET/ICC 301-2019

Ceiling fan energy use is calculated per the Energy Rating Rated Home in ANSI/RESNET/ICC 301-2019.

Note

A reduced cooling setpoint can be specified for summer months when ceiling fans are operating. See HPXML HVAC Control for more information.

HPXML Pools & Hot Tubs¶

HPXML Pools¶

A single pool can be entered as a /HPXML/Building/BuildingDetails/Pools/Pool. If not entered, the simulation will not include a pool.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

Type string See [357] Yes Pool type

[358] Type choices are “in ground”, “on ground”, “above ground”, “other”, “unknown”, or “none”. If “none” is entered, the simulation will not include a pool.

Pool Pump¶

If a pool is specified, a single pool pump can be entered as a Pool/PoolPumps/PoolPump. If not entered, the simulation will not include a pool heater.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

Type string See [358] Yes Pool pump type

Load[Units="kWh/year"]/Value double kWh/yr >= 0 No See [359] Pool pump energy use

extension/UsageMultiplier double >= 0 No 1.0 Multiplier on pool pump energy use

extension/WeekdayScheduleFractions array No See [360] 24 comma-separated weekday fractions

extension/WeekendScheduleFractions array No 24 comma-separated weekend fractions

extension/MonthlyScheduleMultipliers array No See [361] 12 comma-separated monthly multipliers

[359] Type choices are “single speed”, “multi speed”, “variable speed”, “variable flow”, “other”, “unknown”, or “none”. If “none” is entered, the simulation will not include a pool pump.

[360] If Value not provided, defaults based on the 2010 BAHSP: 158.5 / 0.070 * (0.5 + 0.25 * NumberofBedrooms / 3 + 0.35 * ConditionedFloorArea / 1920).

[361] If WeekdayScheduleFractions or WeekendScheduleFractions not provided (and Detailed Schedule Inputs not used), default values from Figure 23 of the 2010 BAHSP are used: “0.003, 0.003, 0.003, 0.004, 0.008, 0.015, 0.026, 0.044, 0.084, 0.121, 0.127, 0.121, 0.120, 0.090, 0.075, 0.061, 0.037, 0.023, 0.013, 0.008, 0.004, 0.003, 0.003, 0.003”.

[362] If MonthlyScheduleMultipliers not provided (and Detailed Schedule Inputs not used), default values from Figure 24 of the 2010 BAHSP are used: “1.154, 1.161, 1.013, 1.010, 1.013, 0.888, 0.883, 0.883, 0.888, 0.978, 0.974, 1.154”.

Pool Heater¶

If a pool is specified, a pool heater can be entered as a Pool/Heater. If not entered, the simulation will not include a pool heater.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

Type string See [362] Yes Pool heater type

Load[Units="kWh/year" or Units="therm/year"]/Value double kWh/yr or therm/yr >= 0 No See [363] Pool heater energy use

extension/UsageMultiplier double >= 0 No 1.0 Multiplier on pool heater energy use

extension/WeekdayScheduleFractions array No See [364] 24 comma-separated weekday fractions

extension/WeekendScheduleFractions array No 24 comma-separated weekend fractions

extension/MonthlyScheduleMultipliers array No See [365] 12 comma-separated monthly multipliers

[363] Type choices are “none, “gas fired”, “electric resistance”, or “heat pump”. If “none” is entered, the simulation will not include a pool heater.

[364]
If Value not provided, defaults as follows:

gas fired: 3.0 / 0.014 * (0.5 + 0.25 * NumberofBedrooms / 3 + 0.35 * ConditionedFloorArea / 1920) (based on the 2010 BAHSP)

electric resistance: 8.3 / 0.004 * (0.5 + 0.25 * NumberofBedrooms / 3 + 0.35 * ConditionedFloorArea / 1920) (based on the 2010 BAHSP)

heat pump: (electric resistance) / 5.0 (based on an average COP of 5 from Energy Saver)

[365] If WeekdayScheduleFractions or WeekendScheduleFractions not provided (and Detailed Schedule Inputs not used), default values from Figure 23 of the 2010 BAHSP are used: “0.003, 0.003, 0.003, 0.004, 0.008, 0.015, 0.026, 0.044, 0.084, 0.121, 0.127, 0.121, 0.120, 0.090, 0.075, 0.061, 0.037, 0.023, 0.013, 0.008, 0.004, 0.003, 0.003, 0.003”.

[366] If MonthlyScheduleMultipliers not provided (and Detailed Schedule Inputs not used), default values from Figure 24 of the 2010 BAHSP are used: “1.154, 1.161, 1.013, 1.010, 1.013, 0.888, 0.883, 0.883, 0.888, 0.978, 0.974, 1.154”.

HPXML Hot Tubs¶

A single hot tub can be entered as a /HPXML/Building/BuildingDetails/HotTubs/HotTub. If not entered, the simulation will not include a hot tub.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

Type string See [366] Yes Hot tub type

[367] Type choices are “in ground”, “on ground”, “above ground”, “other”, “unknown”, or “none”. If “none” is entered, the simulation will not include a hot tub.

Hot Tub Pump¶

If a hot tub is specified, a single hot tub pump can be entered as a HotTub/HotTubPumps/HotTubPump. If not entered, the simulation will not include a hot tub pump.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

Type string See [367] Yes Hot tub pump type

Load[Units="kWh/year"]/Value double kWh/yr >= 0 No See [368] Hot tub pump energy use

extension/UsageMultiplier double >= 0 No 1.0 Multiplier on hot tub pump energy use

extension/WeekdayScheduleFractions array No See [369] 24 comma-separated weekday fractions

extension/WeekendScheduleFractions array No 24 comma-separated weekend fractions

extension/MonthlyScheduleMultipliers array No See [370] 12 comma-separated monthly multipliers

[368] Type choices are “single speed”, “multi speed”, “variable speed”, “variable flow”, “other”, “unknown”, or “none”. If “none” is entered, the simulation will not include a hot tub pump.

[369] If Value not provided, defaults based on the 2010 BAHSP: 59.5 / 0.059 * (0.5 + 0.25 * NumberofBedrooms / 3 + 0.35 * ConditionedFloorArea / 1920).

[370] If WeekdayScheduleFractions or WeekendScheduleFractions not provided (and Detailed Schedule Inputs not used), default values from Figure 23 of the 2010 BAHSP are used: “0.024, 0.029, 0.024, 0.029, 0.047, 0.067, 0.057, 0.024, 0.024, 0.019, 0.015, 0.014, 0.014, 0.014, 0.024, 0.058, 0.126, 0.122, 0.068, 0.061, 0.051, 0.043, 0.024, 0.024”.

[371] If MonthlyScheduleMultipliers not provided (and Detailed Schedule Inputs not used), default values from Figure 24 of the 2010 BAHSP are used: “0.921, 0.928, 0.921, 0.915, 0.921, 1.160, 1.158, 1.158, 1.160, 0.921, 0.915, 0.921”.

Hot Tub Heater¶

If a hot tub is specified, a hot tub heater can be entered as a HotTub/Heater. If not entered, the simulation will not include a hot tub heater.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

Type string See [371] Yes Hot tub heater type

Load[Units="kWh/year" or Units="therm/year"]/Value double kWh/yr or therm/yr >= 0 No See [372] Hot tub heater energy use

extension/UsageMultiplier double >= 0 No 1.0 Multiplier on hot tub heater energy use

extension/WeekdayScheduleFractions array No See [373] 24 comma-separated weekday fractions

extension/WeekendScheduleFractions array No 24 comma-separated weekend fractions

extension/MonthlyScheduleMultipliers array No See [374] 12 comma-separated monthly multipliers

[372] Type choices are “none, “gas fired”, “electric resistance”, or “heat pump”. If “none” is entered, the simulation will not include a hot tub heater.

[373]
If Value not provided, defaults as follows:

gas fired [therm/year]: 0.87 / 0.011 * (0.5 + 0.25 * NumberofBedrooms / 3 + 0.35 * ConditionedFloorArea / 1920) (based on the 2010 BAHSP)

electric resistance [kWh/year]: 49.0 / 0.048 * (0.5 + 0.25 * NumberofBedrooms / 3 + 0.35 * ConditionedFloorArea / 1920) (based on the 2010 BAHSP)

heat pump [kWh/year] = (electric resistance) / 5.0 (based on an average COP of 5 from Energy Saver)

[374] If WeekdayScheduleFractions or WeekendScheduleFractions not provided (and Detailed Schedule Inputs not used), default values from Figure 23 of the 2010 BAHSP are used: “0.024, 0.029, 0.024, 0.029, 0.047, 0.067, 0.057, 0.024, 0.024, 0.019, 0.015, 0.014, 0.014, 0.014, 0.024, 0.058, 0.126, 0.122, 0.068, 0.061, 0.051, 0.043, 0.024, 0.024”.

[375] If MonthlyScheduleMultipliers not provided (and Detailed Schedule Inputs not used), default values from Figure 24 of the 2010 BAHSP are used: “0.837, 0.835, 1.084, 1.084, 1.084, 1.096, 1.096, 1.096, 1.096, 0.931, 0.925, 0.837”.

HPXML Misc Loads¶

Miscellaneous loads are entered in /HPXML/Building/BuildingDetails/MiscLoads.

HPXML Plug Loads¶

Each type of plug load can be entered as a /HPXML/Building/BuildingDetails/MiscLoads/PlugLoad.

It is required to include miscellaneous plug loads (PlugLoadType=”other”), which represents all residual plug loads not explicitly captured elsewhere. It is common to include television plug loads (PlugLoadType=”TV other”), which represents all television energy use in the home. It is less common to include the other plug load types, as they are less frequently found in homes. If not entered, the simulation will not include that type of plug load.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

PlugLoadType string See [375] Yes Type of plug load

Load[Units="kWh/year"]/Value double kWh/yr >= 0 No See [376] Annual electricity consumption

extension/FracSensible double 0 - 1 No See [377] Fraction that is sensible heat gain to conditioned space [378]

extension/FracLatent double 0 - 1 No See [379] Fraction that is latent heat gain to conditioned space

extension/UsageMultiplier double >= 0 No 1.0 Multiplier on electricity use

extension/WeekdayScheduleFractions array No See [380] 24 comma-separated weekday fractions

extension/WeekendScheduleFractions array No See [381] 24 comma-separated weekend fractions

extension/MonthlyScheduleMultipliers array No See [382] 12 comma-separated monthly multipliers

[376] PlugLoadType choices are “other”, “TV other”, “well pump”, or “electric vehicle charging”.

[377]
If Value not provided, defaults as:

other: 0.91 * ConditionedFloorArea (based on ANSI/RESNET/ICC 301-2019)

TV other: 413.0 + 69.0 * NumberofBedrooms (based on ANSI/RESNET/ICC 301-2019)

well pump: 50.8 / 0.127 * (0.5 + 0.25 * NumberofBedrooms / 3 + 0.35 * ConditionedFloorArea / 1920) (based on the 2010 BAHSP)

electric vehicle charging: 1666.67 (calculated using AnnualMiles * kWhPerMile / (ChargerEfficiency * BatteryEfficiency) where AnnualMiles=4500, kWhPerMile=0.3, ChargerEfficiency=0.9, and BatteryEfficiency=0.9)

[378]
If FracSensible not provided, defaults as:

other: 0.855

TV other: 1.0

well pump: 0.0

electric vehicle charging: 0.0

[379] The remaining fraction (i.e., 1.0 - FracSensible - FracLatent) must be > 0 and is assumed to be heat gain outside conditioned space and thus lost.

[380]
If FracLatent not provided, defaults as:

other: 0.045

TV other: 0.0

well pump: 0.0

electric vehicle charging: 0.0

[381]
If WeekdayScheduleFractions not provided (and Detailed Schedule Inputs not used), defaults as:

other: “0.035, 0.033, 0.032, 0.031, 0.032, 0.033, 0.037, 0.042, 0.043, 0.043, 0.043, 0.044, 0.045, 0.045, 0.044, 0.046, 0.048, 0.052, 0.053, 0.05, 0.047, 0.045, 0.04, 0.036” (based on Figure 23 of the 2010 BAHSP)

TV other: “0.037, 0.018, 0.009, 0.007, 0.011, 0.018, 0.029, 0.040, 0.049, 0.058, 0.065, 0.072, 0.076, 0.086, 0.091, 0.102, 0.127, 0.156, 0.210, 0.294, 0.363, 0.344, 0.208, 0.090” (based on the American Time Use Survey)

well pump: “0.044, 0.023, 0.019, 0.015, 0.016, 0.018, 0.026, 0.033, 0.033, 0.032, 0.033, 0.033, 0.032, 0.032, 0.032, 0.033, 0.045, 0.057, 0.066, 0.076, 0.081, 0.086, 0.075, 0.065” (based on Figure 23 of the 2010 BAHSP)

electric vehicle charging: “0.042, 0.042, 0.042, 0.042, 0.042, 0.042, 0.042, 0.042, 0.042, 0.042, 0.042, 0.042, 0.042, 0.042, 0.042, 0.042, 0.042, 0.042, 0.042, 0.042, 0.042, 0.042, 0.042, 0.042”

[382]
If WeekdendScheduleFractions not provided (and Detailed Schedule Inputs not used), defaults as:

other: “0.035, 0.033, 0.032, 0.031, 0.032, 0.033, 0.037, 0.042, 0.043, 0.043, 0.043, 0.044, 0.045, 0.045, 0.044, 0.046, 0.048, 0.052, 0.053, 0.05, 0.047, 0.045, 0.04, 0.036” (based on Figure 23 of the 2010 BAHSP)

TV other: “0.044, 0.022, 0.012, 0.008, 0.011, 0.014, 0.024, 0.043, 0.071, 0.094, 0.112, 0.123, 0.132, 0.156, 0.178, 0.196, 0.206, 0.213, 0.251, 0.330, 0.388, 0.358, 0.226, 0.103” (based on the American Time Use Survey)

well pump: “0.044, 0.023, 0.019, 0.015, 0.016, 0.018, 0.026, 0.033, 0.033, 0.032, 0.033, 0.033, 0.032, 0.032, 0.032, 0.033, 0.045, 0.057, 0.066, 0.076, 0.081, 0.086, 0.075, 0.065” (based on Figure 23 of the 2010 BAHSP)

electric vehicle charging: “0.042, 0.042, 0.042, 0.042, 0.042, 0.042, 0.042, 0.042, 0.042, 0.042, 0.042, 0.042, 0.042, 0.042, 0.042, 0.042, 0.042, 0.042, 0.042, 0.042, 0.042, 0.042, 0.042, 0.042”

[383]
If MonthlyScheduleMultipliers not provided (and Detailed Schedule Inputs not used), defaults as:

other: “1.248, 1.257, 0.993, 0.989, 0.993, 0.827, 0.821, 0.821, 0.827, 0.99, 0.987, 1.248” (based on Figure 24 of the 2010 BAHSP)

TV other: “1.137, 1.129, 0.961, 0.969, 0.961, 0.993, 0.996, 0.96, 0.993, 0.867, 0.86, 1.137” (based on the American Time Use Survey)

well pump: “1.154, 1.161, 1.013, 1.010, 1.013, 0.888, 0.883, 0.883, 0.888, 0.978, 0.974, 1.154” (based on Figure 24 of the 2010 BAHSP)

electric vehicle charging: “1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0”

HPXML Fuel Loads¶

Each fuel load can be entered as a /HPXML/Building/BuildingDetails/MiscLoads/FuelLoad.

It is less common to include fuel load types, as they are less frequently found in homes. If not entered, the simulation will not include that type of fuel load.

Element Type Units Constraints Required Default Notes

SystemIdentifier id Yes Unique identifier

FuelLoadType string See [383] Yes Type of fuel load

Load[Units="therm/year"]/Value double therm/yr >= 0 No See [384] Annual fuel consumption

FuelType string See [385] Yes Fuel type

extension/FracSensible double 0 - 1 No See [386] Fraction that is sensible heat gain to conditioned space [387]

extension/FracLatent double 0 - 1 No See [388] Fraction that is latent heat gain to conditioned space

extension/UsageMultiplier double >= 0 No 1.0 Multiplier on fuel use

extension/WeekdayScheduleFractions array No See [389] 24 comma-separated weekday fractions

extension/WeekendScheduleFractions array No 24 comma-separated weekend fractions

extension/MonthlyScheduleMultipliers array No See [390] 12 comma-separated monthly multipliers

[384] FuelLoadType choices are “grill”, “fireplace”, or “lighting”.

[385]
If Value not provided, calculated as based on the 2010 BAHSP:

grill: 0.87 / 0.029 * (0.5 + 0.25 * NumberofBedrooms / 3 + 0.35 * ConditionedFloorArea / 1920)

fireplace: 1.95 / 0.032 * (0.5 + 0.25 * NumberofBedrooms / 3 + 0.35 * ConditionedFloorArea / 1920)

lighting: 0.22 / 0.012 * (0.5 + 0.25 * NumberofBedrooms / 3 + 0.35 * ConditionedFloorArea / 1920)

[386] FuelType choices are “natural gas”, “fuel oil”, “fuel oil 1”, “fuel oil 2”, “fuel oil 4”, “fuel oil 5/6”, “diesel”, “propane”, “kerosene”, “coal”, “coke”, “bituminous coal”, “anthracite coal”, “wood”, or “wood pellets”.

[387] If FracSensible not provided, defaults to 0.5 for fireplace and 0.0 for all other types.

[388] The remaining fraction (i.e., 1.0 - FracSensible - FracLatent) must be > 0 and is assumed to be heat gain outside conditioned space and thus lost.

[389] If FracLatent not provided, defaults to 0.1 for fireplace and 0.0 for all other types.

[390]
If WeekdayScheduleFractions or WeekendScheduleFractions not provided (and Detailed Schedule Inputs not used), default values from Figure 23 of the 2010 BAHSP are used:

grill: “0.004, 0.001, 0.001, 0.002, 0.007, 0.012, 0.029, 0.046, 0.044, 0.041, 0.044, 0.046, 0.042, 0.038, 0.049, 0.059, 0.110, 0.161, 0.115, 0.070, 0.044, 0.019, 0.013, 0.007”;

fireplace: “0.044, 0.023, 0.019, 0.015, 0.016, 0.018, 0.026, 0.033, 0.033, 0.032, 0.033, 0.033, 0.032, 0.032, 0.032, 0.033, 0.045, 0.057, 0.066, 0.076, 0.081, 0.086, 0.075, 0.065”;

lighting: “0.044, 0.023, 0.019, 0.015, 0.016, 0.018, 0.026, 0.033, 0.033, 0.032, 0.033, 0.033, 0.032, 0.032, 0.032, 0.033, 0.045, 0.057, 0.066, 0.076, 0.081, 0.086, 0.075, 0.065”.

[391]
If MonthlyScheduleMultipliers not provided (and Detailed Schedule Inputs not used), default values from Figure 24 of the 2010 BAHSP are used:

grill: “1.097, 1.097, 0.991, 0.987, 0.991, 0.890, 0.896, 0.896, 0.890, 1.085, 1.085, 1.097”;

fireplace: “1.154, 1.161, 1.013, 1.010, 1.013, 0.888, 0.883, 0.883, 0.888, 0.978, 0.974, 1.154”;

lighting: “1.154, 1.161, 1.013, 1.010, 1.013, 0.888, 0.883, 0.883, 0.888, 0.978, 0.974, 1.154”.

HPXML Locations¶

The various locations used in an HPXML file are defined as follows:

Value Description Temperature Building Type

outside Ambient environment Weather data Any

ground EnergyPlus calculation Any

living space Above-grade conditioned space maintained at setpoint EnergyPlus calculation Any

attic - vented EnergyPlus calculation Any

attic - unvented EnergyPlus calculation Any

basement - conditioned Below-grade conditioned space maintained at setpoint EnergyPlus calculation Any

basement - unconditioned EnergyPlus calculation Any

crawlspace - vented EnergyPlus calculation Any

crawlspace - unvented EnergyPlus calculation Any

crawlspace - conditioned Below-grade conditioned space maintained at setpoint EnergyPlus calculation Any

garage Single-family garage (not shared parking) EnergyPlus calculation Any

other housing unit E.g., conditioned adjacent unit or conditioned corridor Same as living space SFA/MF only

other heated space E.g., shared laundry/equipment space Avg of living space/outside; min of 68F SFA/MF only

other multifamily buffer space E.g., enclosed unconditioned stairwell Avg of living space/outside; min of 50F SFA/MF only

other non-freezing space E.g., shared parking garage ceiling Floats with outside; minimum of 40F SFA/MF only

other exterior Water heater outside Weather data Any

exterior wall Ducts in exterior wall Avg of living space/outside Any

under slab Ducts under slab (ground) EnergyPlus calculation Any

roof deck Ducts on roof deck (outside) Weather data Any

Validating & Debugging Errors¶

When running HPXML files, errors may occur because:

An HPXML file provided is invalid (either relative to the HPXML schema or the EnergyPlus Use Case).
An unexpected EnergyPlus simulation error occurred.

If an error occurs, first look in the run.log for details. If there are no errors in that log file, then the error may be in the EnergyPlus simulation – see eplusout.err.

Contact us if you can’t figure out the cause of an error.

Sample Files¶

Dozens of sample HPXML files are included in the workflow/sample_files directory. The sample files help to illustrate how different building components are described in HPXML.

Each sample file generally makes one isolated change relative to the base HPXML (base.xml) building. For example, the base-dhw-dwhr.xml file adds a DrainWaterHeatRecovery element to the building.

You may find it useful to search through the files for certain HPXML elements or compare (diff) a sample file to the base.xml file.