Fix error if NumberofBedrooms=0 and NumberofBathrooms is omitted

BuildResidentialHPXML/README.md

@@ -76,7 +76,7 @@ Path to the EPW file. Either this or the Zip Code input above must be provided.
 
 **Location: Site Type**
 
-The terrain/shielding of the home, for the infiltration model. Defaults to 'Suburban, Normal' for single-family detached and manufactured home and 'Suburban, Well-Shielded' for single-family attached and apartment units.
+The terrain/shielding of the home, for the infiltration model.
 
 - **Name:** ``location_site_type``
 - **Type:** ``Choice``
@@ -209,7 +209,7 @@ The number of bedrooms in the unit.
 
 **Geometry: Unit Number of Bathrooms**
 
-The number of bathrooms in the unit. Defaults to NumberofBedrooms/2 + 0.5.
+The number of bathrooms in the unit.
 
 - **Name:** ``geometry_unit_num_bathrooms``
 - **Type:** ``Choice``

BuildResidentialHPXML/measure.rb

@@ -80,7 +80,7 @@ def arguments(model) # rubocop:disable Lint/UnusedMethodArgument
 
     arg = OpenStudio::Measure::OSArgument.makeChoiceArgument('location_site_type', choices[:location_site_type], false)
     arg.setDisplayName('Location: Site Type')
-    arg.setDescription("The terrain/shielding of the home, for the infiltration model. Defaults to 'Suburban, Normal' for single-family detached and manufactured home and 'Suburban, Well-Shielded' for single-family attached and apartment units.")
+    arg.setDescription('The terrain/shielding of the home, for the infiltration model.')
     arg.setDefaultValue('Default')
     args << arg
 
@@ -136,7 +136,7 @@ def arguments(model) # rubocop:disable Lint/UnusedMethodArgument
 
     arg = OpenStudio::Measure::OSArgument.makeChoiceArgument('geometry_unit_num_bathrooms', choices[:geometry_unit_num_bathrooms], false)
     arg.setDisplayName('Geometry: Unit Number of Bathrooms')
-    arg.setDescription('The number of bathrooms in the unit. Defaults to NumberofBedrooms/2 + 0.5.')
+    arg.setDescription('The number of bathrooms in the unit.')
     arg.setDefaultValue('Default')
     args << arg
 

BuildResidentialHPXML/measure.xml

@@ -3,8 +3,8 @@
   <schema_version>3.1</schema_version>
   <name>build_residential_hpxml</name>
   <uid>a13a8983-2b01-4930-8af2-42030b6e4233</uid>
-  <version_id>f4f37f65-5e30-41a0-b3dc-7a4a1fa57f44</version_id>
-  <version_modified>2026-05-22T21:28:29Z</version_modified>
+  <version_id>8c6a6855-95e8-491e-8fb6-6820b622531e</version_id>
+  <version_modified>2026-07-17T21:33:32Z</version_modified>
   <xml_checksum>2C38F48B</xml_checksum>
   <class_name>BuildResidentialHPXML</class_name>
   <display_name>HPXML Builder</display_name>
@@ -108,7 +108,7 @@
     <argument>
       <name>location_site_type</name>
       <display_name>Location: Site Type</display_name>
-      <description>The terrain/shielding of the home, for the infiltration model. Defaults to 'Suburban, Normal' for single-family detached and manufactured home and 'Suburban, Well-Shielded' for single-family attached and apartment units.</description>
+      <description>The terrain/shielding of the home, for the infiltration model.</description>
       <type>Choice</type>
       <required>false</required>
       <model_dependent>false</model_dependent>
@@ -595,7 +595,7 @@
     <argument>
       <name>geometry_unit_num_bathrooms</name>
       <display_name>Geometry: Unit Number of Bathrooms</display_name>
-      <description>The number of bathrooms in the unit. Defaults to NumberofBedrooms/2 + 0.5.</description>
+      <description>The number of bathrooms in the unit.</description>
       <type>Choice</type>
       <required>false</required>
       <model_dependent>false</model_dependent>
@@ -11433,7 +11433,7 @@
       <filename>README.md</filename>
       <filetype>md</filetype>
       <usage_type>readme</usage_type>
-      <checksum>40789597</checksum>
+      <checksum>E343E87E</checksum>
     </file>
     <file>
       <filename>README.md.erb</filename>
@@ -11450,7 +11450,7 @@
       <filename>measure.rb</filename>
       <filetype>rb</filetype>
       <usage_type>script</usage_type>
-      <checksum>E3E200DA</checksum>
+      <checksum>93E3B4F6</checksum>
     </file>
     <file>
       <filename>constants.rb</filename>

Changelog.md

@@ -10,6 +10,7 @@ __Bugfixes__
 - **Breaking change**: HPWH `EnergyFactor`/`UniformEnergyFactor` must now be >= 1.45 (previously > 1).
 - Fixes ERV supply outlet enthalpy calculation used to calculate latent effectiveness.
 - Removes duplicated ceiling/floor internal mass surfaces between conditioned stories.
+- Fixes error if `NumberofBedrooms=0` and `NumberofBathrooms` is omitted.
 
 ## OpenStudio-HPXML v1.12.0
 

HPXMLtoOpenStudio/measure.xml

@@ -3,8 +3,8 @@
   <schema_version>3.1</schema_version>
   <name>hpxml_to_openstudio</name>
   <uid>b1543b30-9465-45ff-ba04-1d1f85e763bc</uid>
-  <version_id>b5a80774-bddd-4161-b29c-68607900018d</version_id>
-  <version_modified>2026-07-16T19:57:35Z</version_modified>
+  <version_id>4cdd2955-f813-462c-8e3a-0a9db87b2626</version_id>
+  <version_modified>2026-07-17T21:51:12Z</version_modified>
   <xml_checksum>D8922A73</xml_checksum>
   <class_name>HPXMLToOpenStudio</class_name>
   <display_name>HPXML to OpenStudio Translator</display_name>
@@ -367,7 +367,7 @@
       <filename>defaults.rb</filename>
       <filetype>rb</filetype>
       <usage_type>resource</usage_type>
-      <checksum>4350A1B4</checksum>
+      <checksum>41261A50</checksum>
     </file>
     <file>
       <filename>electric_panel.rb</filename>
@@ -751,7 +751,7 @@
       <filename>test_defaults.rb</filename>
       <filetype>rb</filetype>
       <usage_type>test</usage_type>
-      <checksum>2C65B351</checksum>
+      <checksum>F470D66D</checksum>
     </file>
     <file>
       <filename>test_electric_panel.rb</filename>

HPXMLtoOpenStudio/resources/defaults.rb

@@ -922,7 +922,7 @@ def self.apply_building_construction(hpxml_header, hpxml_bldg)
       hpxml_bldg.building_construction.conditioned_building_volume_isdefaulted = true
     end
     if hpxml_bldg.building_construction.number_of_bathrooms.nil?
-      hpxml_bldg.building_construction.number_of_bathrooms = Float(get_num_bathrooms(nbeds)).to_i
+      hpxml_bldg.building_construction.number_of_bathrooms = get_num_bathrooms(nbeds)
       hpxml_bldg.building_construction.number_of_bathrooms_isdefaulted = true
     end
     if hpxml_bldg.building_construction.number_of_units.nil?
@@ -2820,7 +2820,7 @@ def self.apply_hvac_control(hpxml_bldg, schedules_file, eri_version)
       schedules_file_includes_cooling_setpoint_temp = (schedules_file.nil? ? false : schedules_file.includes_col_name(SchedulesFile::Columns[:CoolingSetpoint].name))
       if hvac_control.cooling_setpoint_temp.nil? && hvac_control.weekday_cooling_setpoints.nil? && !schedules_file_includes_cooling_setpoint_temp
         # No cooling setpoints; set a default cooling setpoint for, e.g., natural ventilation
-        clg_weekday_setpoints, clg_weekend_setpoints = Defaults.get_cooling_setpoint(HPXML::HVACControlTypeManual, eri_version)
+        clg_weekday_setpoints, clg_weekend_setpoints = get_cooling_setpoint(HPXML::HVACControlTypeManual, eri_version)
         if clg_weekday_setpoints.split(', ').uniq.size == 1 && clg_weekend_setpoints.split(', ').uniq.size == 1 && clg_weekday_setpoints.split(', ').uniq == clg_weekend_setpoints.split(', ').uniq
           hvac_control.cooling_setpoint_temp = clg_weekend_setpoints.split(', ').uniq[0].to_f
         else
@@ -4603,7 +4603,7 @@ def self.apply_ceiling_fans(hpxml_bldg, weather, schedules_file)
       ceiling_fan.weekend_fractions_isdefaulted = true
     end
     if ceiling_fan.monthly_multipliers.nil? && !schedules_file_includes_ceiling_fan
-      ceiling_fan.monthly_multipliers = Defaults.get_ceiling_fan_months(weather).join(', ')
+      ceiling_fan.monthly_multipliers = get_ceiling_fan_months(weather).join(', ')
       ceiling_fan.monthly_multipliers_isdefaulted = true
     end
   end
@@ -5483,10 +5483,15 @@ def self.lookup_weather_data_from_wmo(wmo)
   # Gets the default number of bathrooms in the dwelling unit.
   #
   # @param nbeds [Integer] Number of bedrooms in the dwelling unit
-  # @return [Double] Number of bathrooms
+  # @return [Integer] Number of bathrooms
   def self.get_num_bathrooms(nbeds)
     nbaths = nbeds / 2.0 + 0.5 # From BA HSP
-    return nbaths
+
+    # Ensure at least 1 bathroom (which the HPXML schema requires).
+    # Even a studio apartment w/ zero bedrooms would have a bathroom.
+    nbaths = [nbaths, 1].max
+
+    return nbaths.to_i
   end
 
   # Gets the default properties for cooking ranges/ovens.
@@ -6145,7 +6150,7 @@ def self.get_water_heater_performance_adjustment(water_heating_system)
   # @return [Double] Water heater heating capacity (Btu/hr)
   def self.get_water_heater_heating_capacity(fuel, nbeds, num_water_heaters, nbaths = nil)
     if nbaths.nil?
-      nbaths = Defaults.get_num_bathrooms(nbeds)
+      nbaths = get_num_bathrooms(nbeds)
     end
 
     # Adjust the heating capacity if there are multiple water heaters in the home
@@ -6196,7 +6201,7 @@ def self.get_water_heater_tank_volume(fuel, is_hpwh, nbeds, nbaths, n_occ)
     # FUTURE: Incorporate number of occupants for conventional elec/gas storage WHs.
 
     if nbaths.nil?
-      nbaths = Defaults.get_num_bathrooms(nbeds)
+      nbaths = get_num_bathrooms(nbeds)
     end
 
     if is_hpwh && !n_occ.nil? # Heat pump water heater
@@ -7555,7 +7560,7 @@ def self.get_pool_pump_annual_energy(cfa, nbeds, n_occ, unit_type)
       return 0.0
     end
 
-    nbeds_eq = Defaults.get_equivalent_nbeds(nbeds, n_occ, unit_type)
+    nbeds_eq = get_equivalent_nbeds(nbeds, n_occ, unit_type)
 
     return 158.6 / 0.070 * (0.5 + 0.25 * nbeds_eq / 3.0 + 0.25 * cfa / 1920.0)
   end
@@ -7569,7 +7574,7 @@ def self.get_pool_pump_annual_energy(cfa, nbeds, n_occ, unit_type)
   # @param type [String] Type of heater (HPXML::HeaterTypeXXX)
   # @return [Array<String, Double>] Energy units (HPXML::UnitsXXX), annual energy use (kWh/yr or therm/yr)
   def self.get_pool_heater_annual_energy(cfa, nbeds, n_occ, unit_type, type)
-    nbeds_eq = Defaults.get_equivalent_nbeds(nbeds, n_occ, unit_type)
+    nbeds_eq = get_equivalent_nbeds(nbeds, n_occ, unit_type)
 
     load_units = nil
     load_value = nil
@@ -7609,7 +7614,7 @@ def self.get_permanent_spa_pump_annual_energy(cfa, nbeds, n_occ, unit_type)
       return 0.0
     end
 
-    nbeds_eq = Defaults.get_equivalent_nbeds(nbeds, n_occ, unit_type)
+    nbeds_eq = get_equivalent_nbeds(nbeds, n_occ, unit_type)
 
     return 59.5 / 0.059 * (0.5 + 0.25 * nbeds_eq / 3.0 + 0.25 * cfa / 1920.0) # kWh/yr
   end
@@ -7623,7 +7628,7 @@ def self.get_permanent_spa_pump_annual_energy(cfa, nbeds, n_occ, unit_type)
   # @param type [String] Type of heater (HPXML::HeaterTypeXXX)
   # @return [Array<String, Double>] Energy units (HPXML::UnitsXXX), annual energy use (kWh/yr or therm/yr)
   def self.get_permanent_spa_heater_annual_energy(cfa, nbeds, n_occ, unit_type, type)
-    nbeds_eq = Defaults.get_equivalent_nbeds(nbeds, n_occ, unit_type)
+    nbeds_eq = get_equivalent_nbeds(nbeds, n_occ, unit_type)
 
     load_units = nil
     load_value = nil
@@ -7683,7 +7688,7 @@ def self.get_default_well_pump_annual_energy(cfa, nbeds, n_occ, unit_type)
       return 0.0
     end
 
-    nbeds_eq = Defaults.get_equivalent_nbeds(nbeds, n_occ, unit_type)
+    nbeds_eq = get_equivalent_nbeds(nbeds, n_occ, unit_type)
 
     return 50.8 / 0.127 * (0.5 + 0.25 * nbeds_eq / 3.0 + 0.25 * cfa / 1920.0)
   end
@@ -7701,7 +7706,7 @@ def self.get_gas_grill_annual_energy(cfa, nbeds, n_occ, unit_type)
       return 0.0
     end
 
-    nbeds_eq = Defaults.get_equivalent_nbeds(nbeds, n_occ, unit_type)
+    nbeds_eq = get_equivalent_nbeds(nbeds, n_occ, unit_type)
 
     return 0.87 / 0.029 * (0.5 + 0.25 * nbeds_eq / 3.0 + 0.25 * cfa / 1920.0)
   end
@@ -7719,7 +7724,7 @@ def self.get_default_gas_lighting_annual_energy(cfa, nbeds, n_occ, unit_type)
       return 0.0
     end
 
-    nbeds_eq = Defaults.get_equivalent_nbeds(nbeds, n_occ, unit_type)
+    nbeds_eq = get_equivalent_nbeds(nbeds, n_occ, unit_type)
 
     return 0.22 / 0.012 * (0.5 + 0.25 * nbeds_eq / 3.0 + 0.25 * cfa / 1920.0)
   end
@@ -7737,7 +7742,7 @@ def self.get_gas_fireplace_annual_energy(cfa, nbeds, n_occ, unit_type)
       return 0.0
     end
 
-    nbeds_eq = Defaults.get_equivalent_nbeds(nbeds, n_occ, unit_type)
+    nbeds_eq = get_equivalent_nbeds(nbeds, n_occ, unit_type)
 
     return 1.95 / 0.032 * (0.5 + 0.25 * nbeds_eq / 3.0 + 0.25 * cfa / 1920.0)
   end
@@ -7755,7 +7760,7 @@ def self.get_water_use_internal_gains(nbeds, n_occ, unit_type, general_water_use
       return 0.0, 0.0
     end
 
-    nbeds_eq = Defaults.get_equivalent_nbeds(nbeds, n_occ, unit_type)
+    nbeds_eq = get_equivalent_nbeds(nbeds, n_occ, unit_type)
 
     # ANSI/RESNET/ICC 301 - Table 4.2.2(3). Internal Gains for Reference Homes
     sens_gains = (-1227.0 - 409.0 * nbeds_eq) * general_water_use_usage_multiplier # Btu/day

HPXMLtoOpenStudio/tests/test_defaults.rb

@@ -530,6 +530,12 @@ def test_building_construction
     _default_hpxml, default_hpxml_bldg = _test_measure()
     _test_default_building_construction_values(default_hpxml_bldg, 21600, 8.0, 2, 1, -7)
 
+    # Test defaults w/ zero bedrooms
+    hpxml_bldg.building_construction.number_of_bedrooms = 0
+    XMLHelper.write_file(hpxml.to_doc, @tmp_hpxml_path)
+    _default_hpxml, default_hpxml_bldg = _test_measure()
+    _test_default_building_construction_values(default_hpxml_bldg, 21600, 8.0, 1, 1, -7)
+
     # Test defaults w/ belly-and-wing foundation
     hpxml, hpxml_bldg = _create_hpxml('base-foundation-belly-wing-skirt.xml')
     hpxml_bldg.building_construction.conditioned_building_volume = nil

docs/source/workflow_inputs.rst

@@ -651,7 +651,7 @@ Building construction is entered in ``/HPXML/Building/BuildingDetails/BuildingSu
 
   .. [#] If AverageCeilingHeight not provided, defaults to (ConditionedBuildingVolume - ConditionedCrawlspaceVolume) / ConditionedFloorArea if ConditionedBuildingVolume is provided.
          If ConditionedBuildingVolume not provided, AverageCeilingHeight defaults to 8.0 ft (unless there is a cathedral ceiling, in which case the value is adjusted).
-  .. [#] If NumberofBathrooms not provided, calculated as NumberofBedrooms/2 + 0.5 based on the `2010 BAHSP <https://www1.eere.energy.gov/buildings/publications/pdfs/building_america/house_simulation.pdf>`_.
+  .. [#] If NumberofBathrooms not provided, calculated as NumberofBedrooms/2 + 0.5 (rounded down, with a minimum of 1) based on the `2010 BAHSP <https://www1.eere.energy.gov/buildings/publications/pdfs/building_america/house_simulation.pdf>`_.
   .. [#] If ConditionedBuildingVolume not provided, defaults to ConditionedFloorArea * AverageCeilingHeight + ConditionedCrawlspaceVolume.
 
 HPXML Schedules

workflow/hpxml_inputs.json

@@ -1092,6 +1092,11 @@
     "enclosure_floor_over_garage": "Wood Frame, R-38",
     "enclosure_carpet": "80% Carpet"
   },
+  "sample_files/base-enclosure-beds-0.xml": {
+    "parent_hpxml": "sample_files/base.xml",
+    "geometry_unit_num_bedrooms": "0",
+    "geometry_unit_num_bathrooms": "Default"
+  },
   "sample_files/base-enclosure-beds-1.xml": {
     "parent_hpxml": "sample_files/base.xml",
     "geometry_unit_num_bedrooms": "1",