diff --git a/insel/templates/thermal_demand_dynamic_simulation.py b/insel/templates/thermal_demand_dynamic_simulation.py
index 80100d0..ef88cad 100644
--- a/insel/templates/thermal_demand_dynamic_simulation.py
+++ b/insel/templates/thermal_demand_dynamic_simulation.py
@@ -121,7 +121,7 @@ class ThermalDemandDynamicSimulation:
         else:
           n_records += 2
     inputs = [f"{n_hoy}.1"]
-    parameters = [f"{n_records * 13} %[RecLen]",
+    parameters = [f"{n_records * 13 + 1} %[RecLen]",
                   f"'{weather_path}' %[FileName]",
                   f"',' %[Separator]"]
     file = Insel.add_block(file, i_block, 'UBFAST_READD', inputs, parameters)
@@ -131,7 +131,7 @@ class ThermalDemandDynamicSimulation:
     n_ig = i_block
     n_records = number_usage_zones * 6
     inputs = [f"{n_hoy}.1"]
-    parameters = [f"{n_records * 13} %[RecLen]",
+    parameters = [f"{n_records * 13 + 1} %[RecLen]",
                   f"'{ig_path}' %[FileName]",
                   f"',' %[Separator]"]
     file = Insel.add_block(file, i_block, 'UBFAST_READD', inputs, parameters)