diff --git a/hub/exports/building_energy/insel/insel_monthly_energy_balance.py b/hub/exports/building_energy/insel/insel_monthly_energy_balance.py
index e724c445..6f831ac4 100644
--- a/hub/exports/building_energy/insel/insel_monthly_energy_balance.py
+++ b/hub/exports/building_energy/insel/insel_monthly_energy_balance.py
@@ -36,9 +36,12 @@ class InselMonthlyEnergyBalance(Insel):
       file_name_out = building.name + '.out'
       output_path = Path(self._path / file_name_out).resolve()
       if building.internal_zones is not None:
-        self._contents.append(
-          self.generate_meb_template(building, output_path, self._radiation_calculation_method,self._weather_format)
-        )
+        for internal_zone in building.internal_zones:
+          if internal_zone.thermal_zones is None:
+            break
+          self._contents.append(
+            self.generate_meb_template(building, output_path, self._radiation_calculation_method,self._weather_format)
+          )
     self._export()
 
   def _export(self):