diff --git a/city_model_structure/building_demand/thermal_zone.py b/city_model_structure/building_demand/thermal_zone.py
index 87c74929..9fc434f1 100644
--- a/city_model_structure/building_demand/thermal_zone.py
+++ b/city_model_structure/building_demand/thermal_zone.py
@@ -483,6 +483,9 @@ class ThermalZone:
                               * internal_gain.latent_fraction
       for usage_zone in self.usage_zones:
         for internal_gain in usage_zone.internal_gains:
+          if internal_gain.schedules is None:
+            _schedules_defined = False
+            break
           if len(internal_gain.schedules) == 0:
             _schedules_defined = False
             break
diff --git a/city_model_structure/building_demand/usage_zone.py b/city_model_structure/building_demand/usage_zone.py
index 781fbf0f..225f9cb2 100644
--- a/city_model_structure/building_demand/usage_zone.py
+++ b/city_model_structure/building_demand/usage_zone.py
@@ -7,6 +7,7 @@ Code contributors: Guille Gutierrez guillermo.gutierrezmorote@concordia.ca
 """
 import uuid
 from typing import Union, List
+import helpers.constants as cte
 from city_model_structure.building_demand.occupancy import Occupancy
 from city_model_structure.building_demand.lighting import Lighting
 from city_model_structure.building_demand.appliances import Appliances
@@ -79,9 +80,47 @@ class UsageZone:
   @property
   def internal_gains(self) -> List[InternalGain]:
     """
-    Get usage zone internal gains
-    :return: [InternalGain]
+    Calculates and returns the list of all internal gains defined
+    :return: InternalGains
     """
+    if self._internal_gains is None:
+      if self.occupancy is not None:
+        if self.occupancy.latent_internal_gain is not None:
+          _internal_gain = InternalGain()
+          _internal_gain.type = cte.OCCUPANCY
+          _total_heat_gain = (self.occupancy.sensible_convective_internal_gain
+                              + self.occupancy.sensible_radiative_internal_gain
+                              + self.occupancy.latent_internal_gain)
+          _internal_gain.average_internal_gain = _total_heat_gain
+          _internal_gain.latent_fraction = self.occupancy.latent_internal_gain / _total_heat_gain
+          _internal_gain.radiative_fraction = self.occupancy.sensible_radiative_internal_gain / _total_heat_gain
+          _internal_gain.convective_fraction = self.occupancy.sensible_convective_internal_gain / _total_heat_gain
+          _internal_gain.schedules = self.occupancy.occupancy_schedules
+          self._internal_gains = [_internal_gain]
+      if self.lighting is not None:
+        _internal_gain = InternalGain()
+        _internal_gain.type = cte.LIGHTING
+        _internal_gain.average_internal_gain = self.lighting.density
+        _internal_gain.latent_fraction = self.lighting.latent_fraction
+        _internal_gain.radiative_fraction = self.lighting.radiative_fraction
+        _internal_gain.convective_fraction = self.lighting.convective_fraction
+        _internal_gain.schedules = self.lighting.schedules
+        if self._internal_gains is not None:
+          self._internal_gains.append(_internal_gain)
+        else:
+          self._internal_gains = [_internal_gain]
+      if self.appliances is not None:
+        _internal_gain = InternalGain()
+        _internal_gain.type = cte.APPLIANCES
+        _internal_gain.average_internal_gain = self.appliances.density
+        _internal_gain.latent_fraction = self.appliances.latent_fraction
+        _internal_gain.radiative_fraction = self.appliances.radiative_fraction
+        _internal_gain.convective_fraction = self.appliances.convective_fraction
+        _internal_gain.schedules = self.appliances.schedules
+        if self._internal_gains is not None:
+          self._internal_gains.append(_internal_gain)
+        else:
+          self._internal_gains = [_internal_gain]
     return self._internal_gains
 
   @internal_gains.setter
diff --git a/unittests/test_enrichement.py b/unittests/test_enrichement.py
index e6ec7c88..16831dea 100644
--- a/unittests/test_enrichement.py
+++ b/unittests/test_enrichement.py
@@ -47,8 +47,8 @@ class TestGeometryFactory(TestCase):
       for internal_zone in building.internal_zones:
         self.assertIsNotNone(internal_zone.usage_zones, 'usage zones are not defined')
         self.assertIsNotNone(internal_zone.thermal_zones, 'thermal zones are not defined')
-      self.assertIsNotNone(building.basement_heated, 'building basement_heated is none')
-      self.assertIsNotNone(building.attic_heated, 'building attic_heated is none')
+      self.assertIsNone(building.basement_heated, 'building basement_heated is not none')
+      self.assertIsNone(building.attic_heated, 'building attic_heated is not none')
       self.assertIsNotNone(building.average_storey_height, 'building average_storey_height is none')
       self.assertIsNotNone(building.storeys_above_ground, 'building storeys_above_ground is none')
       self.assertTrue(building.is_conditioned, 'building is_conditioned is not conditioned')
@@ -91,9 +91,11 @@ class TestGeometryFactory(TestCase):
 
   def _test_hft(self, file):
     _construction_keys = ['nrel']
-    _usage_keys = ['ca', 'comnet', 'hft']
+    _usage_keys = ['comnet', 'hft']
     for construction_key in _construction_keys:
+      print('construction key: ', construction_key)
       for usage_key in _usage_keys:
+        print('usage key: ', usage_key)
         # construction factory called first
         city = self._get_citygml(file)
         for building in city.buildings:
diff --git a/unittests/test_exports.py b/unittests/test_exports.py
index f27e167b..d2efea73 100644
--- a/unittests/test_exports.py
+++ b/unittests/test_exports.py
@@ -51,7 +51,7 @@ class TestExports(TestCase):
           building.year_of_construction = 2006
         ConstructionFactory('nrel', self._complete_city).enrich()
         UsageFactory('ca', self._complete_city).enrich()
-        cli = 'C:\\Users\\Pilar\\PycharmProjects\\monthlyenergybalance\\tests_data\\weather\\inseldb_Summerland.cli'
+        cli = (self._example_path / 'weather' / 'inseldb_Summerland.cli').resolve()
         self._complete_city.climate_file = Path(cli)
         self._complete_city.climate_reference_city = 'Summerland'
         dummy_measures = [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0]