Windows Transmittance

Frame Simulator, together with Frame Composer, makes windows transmittance computation (applying EN ISO 10077-1 and 10077-2) an extremely easy process. With few and simple steps you will be able to apply finite elements method without the need to know anything about the theory behind it. Frame Simulator is available in English and Italian languages for Windows and MacOSX operating systems.

Do you want to try Frame Simulator?

Frame Simulator Viewer is completely free; you can open and explore any project created with Frame Simulator:

After downloading the sample files above, please open them with Frame Simulator Viewer.

Look how simple it is to get windows transmittance with Frame Simulator:

You’ll find many more videos at our YouTube channel

What’s new in version 4

  • faster and more accurate simulation algorithm;
  • 64bit versions;
  • new and much more flexible report system;
  • a lot of templated to be used for your simulations;
  • totally renewed interface;
  • new visualization options.

Window Transmittance and ISO 10077

Here you are a list of the main features of Frame Simulator, the ideal tool for windows transmittance computation:

  • get extremely accurate results with few and simple operations for every kind of frame; you don’t need to know anything about UNI EN ISO 10077;
  • use finite elements methods without real efforts; the mathematical model is completely hidden to the user;
  • foresee thermal behaviour of frames before producing a prototype;
  • analyze and discover weak points of frames through heat flow visualization;
  • import projects created with other software;
  • send stunning presentations to your clients thanks to the newest features.

EN ISO 10077-2 (2012)

Frame Simulator is certified according to EN ISO 10077-2 norm. Here you are the certification, with all the relative test projects:

Plugins and features for windows transmittance

Since version 3 of Frame Simulator you can expand its capabilities by activating additional plugins, which can be purchased separately.

Import/Export packLBNL Therm import€60 + tax
ISO 15099ISO 15099 cavities, ISO 15099 boundary conditions, ISO 15099 glazing systems€60 + tax

Create your own slide shows!

You will be able to create real slide shows of your projects: simple “record” some screenshots and Frame Simulator will automatically generate an animation. To distribute it, for example, to some clients, is immediate: you just have to make them open your projects, containing the presentation, with the “Viewer” version of the software. This version is completely free and time unlimited, but it can just view files and not modify them.

Fully customizable print report

Forget the old reports: now you can modify and customize reports as you wish. You’ll have an internal editor (similar to the ones you’re familiar with) to define every single detail you want to print. It is even possible to save reports i various file formats (also html, readable by any computer). You’ll be able to insert various kinds of labels, adding more information; it is a key point for a complete documentation.

Frame Simulator is distributed by Dartwin; please visit for more information.

Together with Frame Simulator, we’ll give you for free Frame Composer, useful to compose frames and systems of windows and doors with closures and courtains. Frame Composer can also be purchased alone; please go to Frame Composer’s page for more information.


Here you are a list of blog articles about Frame Simulator: