diff --git a/recommendations/VentilationRecommendations.py b/recommendations/VentilationRecommendations.py
index aa6299e0..07f7cf1e 100644
--- a/recommendations/VentilationRecommendations.py
+++ b/recommendations/VentilationRecommendations.py
@@ -50,16 +50,16 @@ class VentilationRecommendations(Definitions):
 
         part = self.materials.copy()
 
-        estimated_cost = n_units * part[0]["cost"]
+        is_override = "cavity_wall_insulation" in self.property.override
+
+        estimated_cost = n_units * part[0]["cost"] if not is_override else 0
+        labour_hours = 4 * n_units if not is_override else 0
+        labour_days = 4 * n_units / 8.0 if not is_override else 0
 
         part[0]["total"] = estimated_cost
         part[0]["quantity"] = n_units
         part[0]["quantity_unit"] = "part"
 
-        is_override = "cavity_wall_insulation" in cost_result
-        if is_override:
-            cost_result = override_costs(cost_result)
-
         # We recommend installing two mechanical ventilation systems
         self.recommendation = [
             {
@@ -76,7 +76,7 @@ class VentilationRecommendations(Definitions):
                 "energy_cost_savings": 0,
                 "total": estimated_cost,
                 # We use a very simple and rough estimate of 4 hours per unit
-                "labour_hours": 4 * n_units,
-                "labour_days": 4 * n_units / 8.0  # Assume 8 hour day
+                "labour_hours": labour_hours,
+                "labour_days": labour_days  # Assume 8 hour day
             }
         ]