diff --git a/hub/imports/geometry/geojson.py b/hub/imports/geometry/geojson.py
index d8ef97f4..086f2fff 100644
--- a/hub/imports/geometry/geojson.py
+++ b/hub/imports/geometry/geojson.py
@@ -12,7 +12,8 @@ from pyproj import Transformer
 from shapely.geometry import Polygon as ShapelyPolygon
 
 import hub.helpers.constants as cte
-from hub.imports.geometry.helpers.geometry_helper import GeometryHelper
+from hub.helpers.geometry_helper import GeometryHelper
+from hub.imports.geometry.helpers.geometry_helper import GeometryHelper as igh
 from hub.city_model_structure.attributes.polygon import Polygon
 from hub.city_model_structure.building import Building
 from hub.city_model_structure.building_demand.surface import Surface
@@ -62,7 +63,7 @@ class Geojson:
     surfaces = []
     buildings = []
     for zone, surface_coordinates in enumerate(surfaces_coordinates):
-      points = GeometryHelper.points_from_string(GeometryHelper.remove_last_point_from_string(surface_coordinates))
+      points = igh.points_from_string(igh.remove_last_point_from_string(surface_coordinates))
       polygon = Polygon(points)
       surfaces.append(Surface(polygon, polygon, surface_type=cte.GROUND))
       buildings.append(Building(f'{name}_zone_{zone}', surfaces, year_of_construction, function))
@@ -106,6 +107,47 @@ class Geojson:
       polygons.append(transformed_coordinates.lstrip(' '))
       return polygons
 
+  @staticmethod
+  def _find_wall(line_1, line_2):
+    for i in range(0, 2):
+      point_1 = line_1[i]
+      point_2 = line_2[i]
+      distance = GeometryHelper.distance_between_points(point_1, point_2)
+      if distance > 1e-2:
+        return False
+    return True
+
+  def _store_shared_percentage_to_walls(self, city, city_mapped):
+    for building in city.buildings:
+      building_mapped = city_mapped[building.name]
+      for entry in building_mapped:
+        if building_mapped[entry]['shared_points'] <= 3:
+          continue
+        line = [building_mapped[entry]['line_start'], building_mapped[entry]['line_end']]
+        neighbour_line = [building_mapped[entry]['neighbour_line_start'], building_mapped[entry]['neighbour_line_end']]
+        neighbour_height = city.city_object(building_mapped[entry]['neighbour_name']).max_height
+        for wall in building.walls:
+          percentage = 0
+          ground_line = []
+          for point in wall.perimeter_polygon.coordinates:
+            if point[2] < 0.5:
+              ground_line.append(point)
+          # todo: erase when we have no triangulation
+          if len(ground_line) < 2:
+            continue
+          # todo: erase down to here
+          if self._find_wall(line, ground_line):
+            line_shared = (GeometryHelper.distance_between_points(line[0], line[1]) +
+                           GeometryHelper.distance_between_points(neighbour_line[0], neighbour_line[1]) -
+                           GeometryHelper.distance_between_points(line[1], neighbour_line[0]) -
+                           GeometryHelper.distance_between_points(line[0], neighbour_line[1])) / 2
+            percentage = line_shared / GeometryHelper.distance_between_points(line[0], line[1])
+            percentage_height = neighbour_height / building.max_height
+            if percentage_height > 1:
+              percentage_height = 1
+            percentage = percentage * percentage_height
+          wall.percentage_shared = percentage
+
   @property
   def city(self) -> City:
     """