diff --git a/hub/helpers/geometry_helper.py b/hub/helpers/geometry_helper.py
index 912105d4..b61e3b78 100644
--- a/hub/helpers/geometry_helper.py
+++ b/hub/helpers/geometry_helper.py
@@ -59,14 +59,14 @@ class GeometryHelper:
 
   @staticmethod
   def coordinate_to_map_point(coordinate, city):
-    return MapPoint((city.upper_corner[0] - coordinate[0] / 1), (city.upper_corner[1] - coordinate[1] / 1))
+    return MapPoint(((city.upper_corner[0] - coordinate[0]) * 0.5), ((city.upper_corner[1] - coordinate[1]) * 0.5))
 
   @staticmethod
   def city_mapping(city, building_names=None):
     if building_names is None:
       building_names = [b.name for b in city.buildings]
-    x = int((city.upper_corner[0] - city.lower_corner[0]) / 1)
-    y = int((city.upper_corner[1] - city.lower_corner[1]) / 1)
+    x = int((city.upper_corner[0] - city.lower_corner[0]) * 0.5) + 1
+    y = int((city.upper_corner[1] - city.lower_corner[1]) * 0.5) + 1
     city_map = [['' for _ in range(y + 1)] for _ in range(x + 1)]
     img = Image.new('RGB', (x + 1, y + 1), "black")  # create a new black image
     city_image = img.load()  # create the pixel map
@@ -83,11 +83,11 @@ class GeometryHelper:
           distance = GeometryHelper.distance_between_points(coordinate, next_coordinate)
           if distance == 0:
             continue
-          delta_x = (coordinate[0] - next_coordinate[0]) / distance
-          delta_y = (coordinate[1] - next_coordinate[1]) / distance
-          for i in range(0, int(distance)):
-            x = MapPoint(point.x + (delta_x * i), point.y + (delta_y * i)).x
-            y = MapPoint(point.x + (delta_x * i), point.y + (delta_y * i)).y
+          delta_x = (coordinate[0] - next_coordinate[0]) / (distance / 0.5)
+          delta_y = (coordinate[1] - next_coordinate[1]) / (distance / 0.5)
+          for k in range(0, int(distance)):
+            x = MapPoint(point.x + (delta_x * k), point.y + (delta_y * k)).x
+            y = MapPoint(point.x + (delta_x * k), point.y + (delta_y * k)).y
             if city_map[x][y] == '':
               city_map[x][y] = building.name
               city_image[x, y] = (100, 0, 0)
diff --git a/hub/imports/geometry/geojson.py b/hub/imports/geometry/geojson.py
index 21f27b27..d8ef97f4 100644
--- a/hub/imports/geometry/geojson.py
+++ b/hub/imports/geometry/geojson.py
@@ -64,7 +64,7 @@ class Geojson:
     for zone, surface_coordinates in enumerate(surfaces_coordinates):
       points = GeometryHelper.points_from_string(GeometryHelper.remove_last_point_from_string(surface_coordinates))
       polygon = Polygon(points)
-      surfaces.append(Surface(polygon, polygon))
+      surfaces.append(Surface(polygon, polygon, surface_type=cte.GROUND))
       buildings.append(Building(f'{name}_zone_{zone}', surfaces, year_of_construction, function))
     return buildings
 
diff --git a/hub/unittests/test_geometry_factory.py b/hub/unittests/test_geometry_factory.py
index 1c8ef5bb..5ca0e272 100644
--- a/hub/unittests/test_geometry_factory.py
+++ b/hub/unittests/test_geometry_factory.py
@@ -142,7 +142,7 @@ class TestGeometryFactory(TestCase):
     city = self._get_city(file, 'geojson',
                           height_field='citygml_me',
                           year_of_construction_field='ANNEE_CONS',
-                          function_field='LIBELLE_UT')
+                          function_field='CODE_UTILI')
 
     hub.exports.exports_factory.ExportsFactory('obj', city, self._output_path).export()
     self.assertEqual(207, len(city.buildings), 'wrong number of buildings')
@@ -155,7 +155,6 @@ class TestGeometryFactory(TestCase):
     start = datetime.datetime.now()
     file = 'concordia.geojson'
     city = self._get_city(file, 'geojson',
-                          height_field='citygml_me',
                           year_of_construction_field='ANNEE_CONS',
                           function_field='LIBELLE_UT')
     city_end = datetime.datetime.now()