diff --git a/__pycache__/lca_carbon_workflow.cpython-310.pyc b/__pycache__/lca_carbon_workflow.cpython-310.pyc
deleted file mode 100644
index 42c9fa4..0000000
Binary files a/__pycache__/lca_carbon_workflow.cpython-310.pyc and /dev/null differ
diff --git a/building_component_surface.py b/building_component_surface.py
index e69de29..7d648d3 100644
--- a/building_component_surface.py
+++ b/building_component_surface.py
@@ -0,0 +1,48 @@
+"""
+building_component_surface module
+Returns each individual surface values that are needed for
+carbon emission calculation in building_component and eventually in
+lca_carbon_workflow modules.
+SPDX - License - Identifier: LGPL - 3.0 - or -later
+Copyright © 2024 Concordia CERC group
+Code contributors: Alireza Adli alireza.adli@concordia.ca
+Mohammad Reza Seyedabadi mohammad.seyedabadi@mail.concordia.ca
+"""
+
+
+class BuildingComponentSurface:
+  def __init__(self):
+    self._opening_material_emission = None
+    self._opening_surface = None
+    self._envelope_material_emission = None
+    self._envelope_thickness = None
+    self._envelope_surface = None
+
+  @property
+  def opening_material_emission(self):
+    return self._opening_material_emission
+
+  @opening_material_emission.setter
+  def opening_material_emission(self, value):
+    pass
+
+  @property
+  def opening_surface(self):
+    return self._opening_surface
+
+  @opening_surface.setter
+  def opening_surface(self, value):
+    pass
+
+  @property
+  def envelope_material_emission(self):
+    return self._envelope_material_emission
+
+  @property
+  def envelope_thickness(self):
+    return self._envelope_thickness
+
+  @property
+  def envelope_surface(self):
+    return self._envelope_surface
+
diff --git a/lca_carbon_workflow.py b/lca_carbon_workflow.py
index 23d500b..079f157 100644
--- a/lca_carbon_workflow.py
+++ b/lca_carbon_workflow.py
@@ -1,5 +1,5 @@
 """
-building_component module
+lca_carbon_workflow module
 Returns the summarize of envelope and energy systems
 SPDX - License - Identifier: LGPL - 3.0 - or -later
 Copyright © 2024 Concordia CERC group
@@ -40,6 +40,23 @@ class LCACarbonWorkflow:
     print(f'city created from {self.file_path}')
     ConstructionFactory(self.handler, self.city).enrich()
 
-  def calculate_emission(self):
-    for building in self.city.buildings:
-      return len(building.surfaces)
+  @staticmethod
+  def calculate_opening_emission(building):
+    surface_emission = []
+    for surface in building.surfaces:
+      if surface.window_ratio == 0:
+        opening_surface = 0
+        opening_material_emission = 0
+      else:
+        opening_surface = 0
+        opening_material_emission = 0
+        for opening in surface.associated_thermal_boundaries.thermal_openings:
+          opening_surface += opening.area
+          opening_material_emission =
+
+
+
+# def calculate_emission(self):
+  #   emitted_carbon = []
+  #   for building in self.city.buildings:
+  #     return len(building.surfaces)