diff --git a/backend/Property.py b/backend/Property.py
index 956dd586..580dbb89 100644
--- a/backend/Property.py
+++ b/backend/Property.py
@@ -350,7 +350,19 @@ class Property:
                 r for r in property_representative_recommendations
                 if r["phase"] <= phase
             ]
-            epc_transformations = [x["description_simulation"] for x in represenative_recs_to_this_phase]
+            # TODO: This is placeholder, but it's to handle the case of having both internal and external wall
+            #       insulation as options. This will cause the process below to fall over, so we take just
+            #       external wall insulation in epc_transformations, if we have both
+            types = [
+                x["type"] for x in represenative_recs_to_this_phase
+            ]
+            if "external_wall_insulation" in types and "internal_wall_insulation" in types:
+                epc_transformations = [
+                    x["description_simulation"] for x in represenative_recs_to_this_phase if
+                    x["type"] != "internal_wall_insulation"
+                ]
+            else:
+                epc_transformations = [x["description_simulation"] for x in represenative_recs_to_this_phase]
 
             # It is possible that we could have two simulations applied to the same descriptions
             # We extract these out