diff --git a/packages/domain/src/domain/sap/worksheet/heat_transmission.py b/packages/domain/src/domain/sap/worksheet/heat_transmission.py
index 37a3f935..1c302c61 100644
--- a/packages/domain/src/domain/sap/worksheet/heat_transmission.py
+++ b/packages/domain/src/domain/sap/worksheet/heat_transmission.py
@@ -496,12 +496,26 @@ def heat_transmission_from_cert(
                 age_band=age_band, insulation_thickness_mm=floor_ins_thickness
             )
         else:
+            # The per-bp `floor_construction_type` lodgement ("Suspended
+            # timber" / "Solid") takes precedence over the global
+            # `epc.floors[].description` when present — it's the explicit
+            # per-part lodgement Elmhurst surfaces in §3 / §9 of the
+            # Summary PDF (cf. cert 001479 Main: floor_construction_type
+            # = "Suspended timber" age C; the cascade's `u_floor`
+            # otherwise defaults to the solid branch for age bands C+
+            # without an explicit signal, producing a U=0.60 vs the
+            # worksheet's suspended-timber U=0.65).
+            effective_floor_description = (
+                part.floor_construction_type
+                if part.floor_construction_type
+                else floor_description
+            )
             uf = u_floor(
                 country=country, age_band=age_band, construction=floor_construction,
                 insulation_thickness_mm=floor_ins_thickness,
                 area_m2=floor_area, perimeter_m=floor_perimeter,
                 wall_thickness_mm=part.wall_thickness_mm,
-                description=floor_description,
+                description=effective_floor_description,
             )
         upw = u_party_wall(party_wall_construction=party_construction)
         # Per-bp `y` for backwards compat: when the bp's own age band