Fritted Glass Modeling

Last Updated: Friday, March 28, 2025

Software/Versions Affected:

  • WINDOW›7

WINDOW 7.8 has deprecated the old (WINDOW 6.3) methodology for modeling fritted glass and replaced it with the implementation of the direct-diffuse (dir/dif) method for light-scattering data, starting with WINDOW 7.8.71.

This direct-diffuse method requires submitting data for the product to the Complex Glazing Database (CGDB), and those products are contained in the Shade Material and Shading Layer Libraries in WINDOW.

Examples of these direct-diffuse layers, and a general overview is found on our web site in the CGDB section Submitting Data to the CGDB, under the "CGDB Diffuse glazing submission process" section

Detailed instructions about measurement is given in NFRC 300 and 301 technical documents available from the National Fenestration Rating Council (NFRC) on their Technical Documents web page.

Using the metholdogy desribed in those documents, it is possible to create a custom direct-diffuse product and import it into the WINDOW Shade Material Library. 

WINDOW Direct-Diffuse Import

After importing a product into the Shade Material Library, a companion Shading Layer Library record is automatically generated.

WINDOW Direct-Diffuse Shading Layer

The ability to modify the substrate of these light-scattering products has not yet been implemented.

To add a direct-diffuse layer to a glazing system, make sure to change the "Glass<n>" to "Shade<n>" in the layer you want to add the dir/dif layer, and then you can add records from the Shading Layer Library with the double arrow (to see the list) or by typing the ID number in the ID column.