The Window as a “Solar Panel”: Light Transmittance & Solar Factor G

With this article, we cover two very important aspects of glazings: light transmission and the solar heat gain coefficient. These parameters are extremely important for performing buildings and passive houses, however they are often overlooked by both designers and window…

The glass edge thermal bridge: the PSIg value

We continue our series of articles on thermal efficiency of windows, describing the glass edge thermal bridge. As far as thermal bridges go, this one is inevitable, and it represents the weakest point of a well designed thermal envelope. It…

Thermal Transmittance U vs Th. Resistance R

To achieve thermal comfort and energy efficiency in buildings, a primary role is played by the thermal envelope: this is required to thermally decouple the indoor environment from the ever-changing external conditions, both in summer and in winter. The structures…

What’s an insulation material?

With more and more people talking about building energy efficiency and passive houses, it has become more and more common to hear about insulation. In this article, we explain what an insulation material is, to try and shed some light……

Thermal bridges: the temperature factor fRsi

We continue our series of articles on the topic of thermal bridges: this time, we illustrate the fRsi value, which describes the thermal ”strenght” of a node under the point of view of internal surface temperatures. As we have explained…

Thermal bridges: the PSI value

For new builds as well as energy retrofits, worldwide the construction industry is shifting more and more towards zero energy buildings and Passive Houses. With the thermal envelope becoming more and more advanced, the correct evaluation of thermal bridges becomes…

The compactness ratio or Form Factor of a building

When addressing the energy efficiency of a building, one of the most important players in the game is the compactness of its thermal envelope. Is there a way to measure the compactness of a building? Yes: it’s the compactness ratio.