diff --git a/lca_carbon_workflow.py b/lca_carbon_workflow.py
index 99c4376..35926a6 100644
--- a/lca_carbon_workflow.py
+++ b/lca_carbon_workflow.py
@@ -51,7 +51,7 @@ class LCACarbonWorkflow:
     print(f'city created from {self.file_path}')
     ConstructionFactory(self.handler, self.city).enrich()
 
-  def calculate_opening_emission(self, building):
+  def calculate_building_component_emission(self, building):
     surface_opening_emission = []
     period_of_construction = self.nrcan_catalogs.year_to_period_of_construction(building.year_of_construction)
     print(period_of_construction)
@@ -72,26 +72,32 @@ class LCACarbonWorkflow:
           # print('window = 0')
         else:
           print('window != 0')
-          for opening in boundary.thermal_openings:
-            transparent_surface_type = 'Window'
-            if building.year_of_construction >= 2020 and \
-                    surface.type == 'Roof':
-              transparent_surface_type = 'Skylight'
-            opening_emission.append(OpeningEmission(
-              self.nrcan_catalogs.search_transparent_surfaces(
-                transparent_surface_type, opaque_surface_code)['embodied_carbon'],
-              opening.area).calculate_opening_emission())
-            print('\t\t\t', opening_emission)
-          print('opening_emission', opening_emission)
+          opening_emission = self._calculate_opening_emission(
+            building, surface, boundary, opaque_surface_code)
         if opening_emission:
           boundary_opening_emission += opening_emission
         print('boundary_opening_emission', boundary_opening_emission)
       if boundary_opening_emission:
         surface_opening_emission += boundary_opening_emission
-      print('surface_opening_emission', surface_opening_emission, '\n', sum(surface_opening_emission))
+      building_opening_emission = sum(surface_opening_emission)
+      print(building_opening_emission)
+
+  def _calculate_opening_emission(
+          self, building, surface, boundary, opaque_surface_code):
+    opening_emission = []
+    for opening in boundary.thermal_openings:
+      transparent_surface_type = 'Window'
+      if building.year_of_construction >= 2020 and \
+              surface.type == 'Roof':
+        transparent_surface_type = 'Skylight'
+      opening_emission.append(OpeningEmission(
+        self.nrcan_catalogs.search_transparent_surfaces(
+          transparent_surface_type, opaque_surface_code)['embodied_carbon'],
+        opening.area).calculate_opening_emission())
+    return opening_emission
 
   def calculate_emission(self):
     emitted_carbon = []
     opening_emission = []
     for building in self.city.buildings:
-      self.calculate_opening_emission(building)
+      self.calculate_building_component_emission(building)