Numfem Therm, first start


After Numfem Therm installation, a new ribbon tab “Numfem.Therm” is visible in Revit. 

Settings dialog

Numfem Therm relies on Revit parameters (global, project and shared).

To ensure analysis can be done, it is necessary to create and assign at least the following global parameters :

  • The external temperature
  • The internal temperature for rooms/spaces
  • The default internal temperature

There are many other settings which give you complete freedom to use Numfem Therm according to your way of working.

The “import” button makes possible to import settings either from an exiting project (rvt) or from a existing template project (rte). We decided not to provide any template project because it greatly dependents on your needs.

Callout & analysis

Numfem Therm can analyze Revit callouts (plan, section) with the logic “what you see is what you get”.

Beware that the analysed view is the callout’s view, not the view the callout belongs to.

You can add/remove specific details by using filled/masking regions inside the callout view.

Don’t forget to assign a material to these details, thanks to a specific “material” parameter, and to make the link to that parameter in Numfem Therm’s Options.

Snapping & dimensions

Dimensions in a callout are used to define the related lengths for Psi value calculation.

By default, dimensions cannot snap to callout boundaries, but you can use the “magnet” button to automatically create detail lines following those boundaries, and then have your dimensions snap to these lines.


The analysis button is only active when :

  1. Numfem Therm standalone is launched and waiting for instructions (not busy, valid license, …).
  2. You have selected a callout.