diff --git a/datatypes/epc/domain/tests/test_from_sap_schema.py b/datatypes/epc/domain/tests/test_from_sap_schema.py
index dd8f021dd..5eb64a6ab 100644
--- a/datatypes/epc/domain/tests/test_from_sap_schema.py
+++ b/datatypes/epc/domain/tests/test_from_sap_schema.py
@@ -95,6 +95,17 @@ class TestFromSapSchema17_1RebaselineFields:
 
         assert result.sap_version == 9.92
 
+    def test_maps_property_type_as_gov_code_string(self) -> None:
+        # property_type feeds the calculator (heat_transmission `_is_house` /
+        # `_is_flat_or_maisonette` drive party-wall + heat-loss handling). Left
+        # None, the dwelling is classified as neither → degraded SAP. The fixture
+        # is a flat (gov code 2); mapped as a string like from_rdsap_schema_17_1.
+        schema = from_dict(SapSchema17_1, load("sap_17_1.json"))
+
+        result = EpcPropertyDataMapper.from_sap_schema_17_1(schema)
+
+        assert result.property_type == "2"
+
 
 class TestFullSapHasHotWaterCylinderFallback:
     """Some full-SAP certs (e.g. SAP-Schema-17.0 cert 8265-7433-3220-9736-7902)