diff --git a/backend/Property.py b/backend/Property.py
index 09c1d8ed..14f7e03f 100644
--- a/backend/Property.py
+++ b/backend/Property.py
@@ -553,7 +553,7 @@ class Property:
                 "internal_wall_insulation", "external_wall_insulation", "cavity_wall_insulation",
                 "cylinder_thermostat", "loft_insulation", "room_roof_insulation", "flat_roof_insulation",
                 "solid_floor_insulation", "suspended_floor_insulation", "mixed_glazing",
-                "windows_glazing", "mechanical_ventilation", "solar_pv"
+                "windows_glazing", "mechanical_ventilation", "solar_pv", "sloping_ceiling_insulation"
             ]:
                 # We update the data, as defined in the recommendaton
                 for prefix in ["walls", "roof", "floor"]: