This is just to remind on time, at the beginning of 2014, that old BF-data sheets “Psi-values for windows” with representative Psi-values simulated from individual material values have lost their validity. According to a decision of the BF Working Group “Warm Edge”, from now on only data sheets with Psi-values determined with the measured equivalent thermal conductivity of the spacer are valid.

My recommendation: Do not save data sheet copies locally on your computer. In case of need just download the data sheets always newly from the website of the BF Bundesverband Flachglas. This will ensure that you are always up-to-date.

You can find the link on my literature list, or directly here.