diff --git a/domain/epc/property_overrides/roof_type.py b/domain/epc/property_overrides/roof_type.py
index bc3073f86..59437c91d 100644
--- a/domain/epc/property_overrides/roof_type.py
+++ b/domain/epc/property_overrides/roof_type.py
@@ -70,6 +70,33 @@ class RoofType(Enum):
     PITCHED_LOFT_400MM = "Pitched, 400 mm loft insulation"
     PITCHED_LOFT_400_PLUS_MM = "Pitched, 400+ mm loft insulation"
 
+    # A pitched roof whose ceiling follows the slope (gov-API roof_construction
+    # code 8) — no loft void, so its insulation sits at the rafter/slope line, NOT
+    # on horizontal ceiling joists. Distinct from both the PITCHED_LOFT_* ladder
+    # (loft joists) and PITCHED_INSULATED_AT_RAFTERS (a rafter-cavity over a loft).
+    # "as built" defers the insulation assumption to the construction age band
+    # (Table 18 col (3) via `is_pitched_sloping_ceiling`); the mm ladder carries
+    # the depth into the overlay, scored on Table 17 col (1a) "insulated slope".
+    # The value column is an FE-owned pgEnum kept lock-step with
+    # assessment-model#449 / migration 0278 (ADR-0002, ADR-0066).
+    PITCHED_SLOPING_CEILING_AS_BUILT = "Pitched, sloping ceiling, as built"
+    PITCHED_SLOPING_CEILING_12MM = "Pitched, sloping ceiling, 12 mm insulation"
+    PITCHED_SLOPING_CEILING_25MM = "Pitched, sloping ceiling, 25 mm insulation"
+    PITCHED_SLOPING_CEILING_50MM = "Pitched, sloping ceiling, 50 mm insulation"
+    PITCHED_SLOPING_CEILING_75MM = "Pitched, sloping ceiling, 75 mm insulation"
+    PITCHED_SLOPING_CEILING_100MM = "Pitched, sloping ceiling, 100 mm insulation"
+    PITCHED_SLOPING_CEILING_125MM = "Pitched, sloping ceiling, 125 mm insulation"
+    PITCHED_SLOPING_CEILING_150MM = "Pitched, sloping ceiling, 150 mm insulation"
+    PITCHED_SLOPING_CEILING_175MM = "Pitched, sloping ceiling, 175 mm insulation"
+    PITCHED_SLOPING_CEILING_200MM = "Pitched, sloping ceiling, 200 mm insulation"
+    PITCHED_SLOPING_CEILING_225MM = "Pitched, sloping ceiling, 225 mm insulation"
+    PITCHED_SLOPING_CEILING_250MM = "Pitched, sloping ceiling, 250 mm insulation"
+    PITCHED_SLOPING_CEILING_270MM = "Pitched, sloping ceiling, 270 mm insulation"
+    PITCHED_SLOPING_CEILING_300MM = "Pitched, sloping ceiling, 300 mm insulation"
+    PITCHED_SLOPING_CEILING_350MM = "Pitched, sloping ceiling, 350 mm insulation"
+    PITCHED_SLOPING_CEILING_400MM = "Pitched, sloping ceiling, 400 mm insulation"
+    PITCHED_SLOPING_CEILING_400_PLUS = "Pitched, sloping ceiling, 400+ mm insulation"
+
     ROOF_ROOM_INSULATED = "Roof room(s), insulated"
     ROOF_ROOM_INSULATED_ASSUMED = "Roof room(s), insulated (assumed)"
     ROOF_ROOM_LIMITED_INSULATION = "Roof room(s), limited insulation"