diff --git a/Changelog.md b/Changelog.md
index e533f038a2..d0e42dd881 100644
--- a/Changelog.md
+++ b/Changelog.md
@@ -7,7 +7,7 @@ __Features__
 
 __Bugfixes__
 - **Breaking change**: Prevent possible error if HPWH in confined space with very small containment volume; minimum allowed volume now 32 ft3.
-- **Breaking change**: HPWH `EnergyFactor`/`UniformEnergyFactor` must now be >= 2 (previously > 1).
+- **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.
 
diff --git a/HPXMLtoOpenStudio/measure.xml b/HPXMLtoOpenStudio/measure.xml
index e06fb34c93..9799256f7b 100644
--- a/HPXMLtoOpenStudio/measure.xml
+++ b/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>33bfdc9e-84c0-409d-bc66-ca2781e23cf0</version_id>
-  <version_modified>2026-07-15T22:44:01Z</version_modified>
+  <version_id>b5a80774-bddd-4161-b29c-68607900018d</version_id>
+  <version_modified>2026-07-16T19:57:35Z</version_modified>
   <xml_checksum>D8922A73</xml_checksum>
   <class_name>HPXMLToOpenStudio</class_name>
   <display_name>HPXML to OpenStudio Translator</display_name>
@@ -421,7 +421,7 @@
       <filename>hpxml_schematron/EPvalidator.sch</filename>
       <filetype>sch</filetype>
       <usage_type>resource</usage_type>
-      <checksum>423C115C</checksum>
+      <checksum>277C72EB</checksum>
     </file>
     <file>
       <filename>hpxml_schematron/iso-schematron.xsd</filename>
@@ -829,7 +829,7 @@
       <filename>test_validation.rb</filename>
       <filetype>rb</filetype>
       <usage_type>test</usage_type>
-      <checksum>F7D696DC</checksum>
+      <checksum>9ABBBD64</checksum>
     </file>
     <file>
       <filename>test_vehicle.rb</filename>
diff --git a/HPXMLtoOpenStudio/resources/hpxml_schematron/EPvalidator.sch b/HPXMLtoOpenStudio/resources/hpxml_schematron/EPvalidator.sch
index 7d33a86035..65471360e5 100644
--- a/HPXMLtoOpenStudio/resources/hpxml_schematron/EPvalidator.sch
+++ b/HPXMLtoOpenStudio/resources/hpxml_schematron/EPvalidator.sch
@@ -2139,8 +2139,9 @@
       <sch:assert role='ERROR' test='count(h:FractionDHWLoadServed) = 1'>Expected FractionDHWLoadServed</sch:assert>
       <sch:assert role='ERROR' test='number(h:HeatingCapacity) &gt; 0 or not(h:HeatingCapacity)'>Expected HeatingCapacity to be greater than 0.</sch:assert>
       <sch:assert role='ERROR' test='count(h:UniformEnergyFactor) + count(h:EnergyFactor) = 1'>Expected UniformEnergyFactor or EnergyFactor but not both</sch:assert>
-      <sch:assert role='ERROR' test='number(h:UniformEnergyFactor) &gt;= 2 or not(h:UniformEnergyFactor)'>Expected UniformEnergyFactor to be greater than or equal to 2</sch:assert>
-      <sch:assert role='ERROR' test='number(h:EnergyFactor) &gt;= 2 or not(h:EnergyFactor)'>Expected EnergyFactor to be greater than or equal to 2</sch:assert>
+      <!-- Note: We need to allow modeling HPWHs w/ EF/UEF around 1.5 for ENERGY STAR and DOE Efficient New Home ERI targets -->
+      <sch:assert role='ERROR' test='number(h:UniformEnergyFactor) &gt;= 1.45 or not(h:UniformEnergyFactor)'>Expected UniformEnergyFactor to be greater than or equal to 1.45</sch:assert>
+      <sch:assert role='ERROR' test='number(h:EnergyFactor) &gt;= 1.45 or not(h:EnergyFactor)'>Expected EnergyFactor to be greater than or equal to 1.45</sch:assert>
       <sch:assert role='ERROR' test='h:HPWHOperatingMode[text()="hybrid/auto" or text()="heat pump only"] or not(h:HPWHOperatingMode)'>Expected HPWHOperatingMode to be 'hybrid/auto' or 'heat pump only'</sch:assert>
       <sch:assert role='ERROR' test='count(h:extension/h:HPWHInConfinedSpaceWithoutMitigation) &lt;= 1'>Expected at most one extension/HPWHInConfinedSpaceWithoutMitigation</sch:assert>
       <sch:assert role='ERROR' test='h:extension/h:HPWHInConfinedSpaceWithoutMitigation[text()="true" or text()="false"] or not(h:extension/h:HPWHInConfinedSpaceWithoutMitigation)'>Expected extension/HPWHInConfinedSpaceWithoutMitigation to be 'true' or 'false'</sch:assert>
diff --git a/HPXMLtoOpenStudio/tests/test_validation.rb b/HPXMLtoOpenStudio/tests/test_validation.rb
index 53c3a49d00..2504826d54 100644
--- a/HPXMLtoOpenStudio/tests/test_validation.rb
+++ b/HPXMLtoOpenStudio/tests/test_validation.rb
@@ -75,7 +75,7 @@ def test_schema_schematron_error_messages
                             'dehumidifier-fraction-served' => ['Expected sum(FractionDehumidificationLoadServed) to be less than or equal to 1 [context: /HPXML/Building/BuildingDetails, id: "MyBuilding"]'],
                             'dhw-frac-load-served' => ['Expected sum(FractionDHWLoadServed) to be 1 [context: /HPXML/Building/BuildingDetails, id: "MyBuilding"]'],
                             'dhw-invalid-ef-tank' => ['Expected EnergyFactor to be less than 1 [context: /HPXML/Building/BuildingDetails/Systems/WaterHeating/WaterHeatingSystem[WaterHeaterType="storage water heater"], id: "WaterHeatingSystem1"]'],
-                            'dhw-invalid-uef-tank-heat-pump' => ['Expected UniformEnergyFactor to be greater than or equal to 2 [context: /HPXML/Building/BuildingDetails/Systems/WaterHeating/WaterHeatingSystem[WaterHeaterType="heat pump water heater"], id: "WaterHeatingSystem1"]'],
+                            'dhw-invalid-uef-tank-heat-pump' => ['Expected UniformEnergyFactor to be greater than or equal to 1.45 [context: /HPXML/Building/BuildingDetails/Systems/WaterHeating/WaterHeatingSystem[WaterHeaterType="heat pump water heater"], id: "WaterHeatingSystem1"]'],
                             'dishwasher-location' => ['A location is specified as "garage" but no surfaces were found adjacent to this space type.'],
                             'duct-leakage-cfm25' => ["The value '-2.0' is less than the minimum value allowed",
                                                      "The value '-3.0' is less than the minimum value allowed"],
@@ -326,7 +326,7 @@ def test_schema_schematron_error_messages
         hpxml_bldg.water_heating_systems[0].recovery_efficiency = nil
       when 'dhw-invalid-uef-tank-heat-pump'
         hpxml, hpxml_bldg = _create_hpxml('base-dhw-tank-heat-pump.xml')
-        hpxml_bldg.water_heating_systems[0].uniform_energy_factor = 1.5
+        hpxml_bldg.water_heating_systems[0].uniform_energy_factor = 1.4
       when 'dishwasher-location'
         hpxml, hpxml_bldg = _create_hpxml('base.xml')
         hpxml_bldg.dishwashers[0].location = HPXML::LocationGarage
diff --git a/docs/source/workflow_inputs.rst b/docs/source/workflow_inputs.rst
index d08c699ef2..0bff88401d 100644
--- a/docs/source/workflow_inputs.rst
+++ b/docs/source/workflow_inputs.rst
@@ -4241,7 +4241,7 @@ Each heat pump water heater is entered as a ``/HPXML/Building/BuildingDetails/Sy
   ``FractionDHWLoadServed``                            double            frac           >= 0, <= 1 [#]_         Yes                       Fraction of hot water load served [#]_
   ``HeatingCapacity``                                  double            Btu/hr         > 0                     No        See [#]_        Heating input capacity
   ``BackupHeatingCapacity``                            double            Btu/hr         >= 0                    No        15355 (4.5 kW)  Heating capacity of the electric resistance backup
-  ``UniformEnergyFactor`` or ``EnergyFactor``          double            frac           >= 2, <= 5              Yes                       EnergyGuide label rated efficiency
+  ``UniformEnergyFactor`` or ``EnergyFactor``          double            frac           >= 1.45, <= 5           Yes                       EnergyGuide label rated efficiency
   ``HPWHDucting/ExhaustAirTermination``                string                           See [#]_                No        <none>          The location where HPWH exhaust air is ducted to
   ``HPWHOperatingMode``                                string                           See [#]_                No        hybrid/auto     Operating mode [#]_
   ``UsageBin`` or ``FirstHourRating``                  string or double  str or gal/hr  See [#]_ or > 0         No        See [#]_        EnergyGuide label usage bin/first hour rating