March 18th, 2013. Further to my previous announcement, ift Rosenheim, Germany, has published another ift-guideline about warm edge: WA 17/1 “Thermally improved spacers – Part 2: Determination of the equivalent thermal conductivity by means of measurement”. This guideline is a result from the latest research project of the working group “Warm Edge” of the German association Bundesverband Flachglas (BF). The guideline explains how to determine the so-called equivalent thermal conductivity value λeq,2B of a spacer and how to use it for the simulation of Ψ-values of windows according to EN ISO 10077-2, instead of a detailed geometrical spacer model with a multitude of individual conductivity values of the spacer constituents.

In comparison, this is a simple and pragmatic solution for obtaining of spacer input data for individual simulations. It helps to avoid mistakes with the modelling of rather complex spacer geometries. Furthermore, from now on, the “representative Ψ-values”, published on the BF data sheets “Psi-values for windows” will be determined according to this guideline.

The ift-guideline can be ordered in German language here. An English version will follow soon.