Heating and Cooling Load Anlaysis

Hi @chris and @mostapha,

I’ve created a bay study to analyse different heating and cooling load for individual facade options available following up your online tutorials and this forum.

I modified some steps as defining the thermal properties of construction (rather than 90.1 libraries), user profiles and weather data ( Using CIBSE verified .epw locally).

I don’t get any errors but can not get the expected results to compare with some other modelling software. I’m sure missing something.

Is there a route to validate the progress?

Thanks in advance,



If you are in the UK and try to replicate IES, Tas laods against e+ I am afraid this will not match easily with e+/OpenStudio as there is much more complexity and choices.

try to get some testing model for ASHRAE 140-1 and validate this… or see if software providers can give you validation models.

here some links:



Thanks Michal! I’ll definitely look into it.

@btanriverdi ,

Given that you’re referencing the ASHRAE 90.1 construction sets, I am going to assume that you are using the LBT plugin and not the legacy one.

I think it would first help to clarify what type of heating + cooling loads you are trying to match. For example, is it an annual load or a peak load over a particular design day.

Second, it would help to clarify which of the simulation inputs you have tried to match, including:

  1. Schedules for occupancy, lighting, equipment, etc.
  2. Density of occupants and internal loads.
  3. Setpoint schedules.
  4. Infiltration values
  5. Ideal air system properties (eg. economizers, heat recovery, etc.)

FYI, the “HB Thermal Load Balance” component can help you understand what terms of the balance are driving your heating + cooling so that you can see what might not be matching your other model.

Hi @chris;

Thanks for your reply. Yes, I’m using the LBT plugin not the legacy one.

Let me open up the subject more,

I created a circuit that use inputs;
-HB Opaque construction element for U values of all solid surfaces

  • HB Window construction element for U and g values of glazing
    -All HVAC (set point) and occupany/internal gain and air exchange related profiles ( internal / air profiles are turned off as the study is for understanding the fabric only loads)
    -As using CIBSE purchased weather files, a local .epw connection. I used the from epw to ddy generator to create the ddy info required.

I’m trying to run HB Model to OSM ( which run the simulation properly)

Main goal is to reach the peak loads coming from fabric heating and cooling loads ( to understand the demand)

PS: I tried the HB Thermal Balance as well. The annual graph looks fine (the heating cooling required times) however the numbers are quite low to expected.

Attached the script
BT baystudy_annual_loads_WIP_deconstruct.gh (159.3 KB)