Thermal bridging of I-Joist vs Larsen Truss
I-Joist vs Larsen Truss: Does it make a difference for exterior high R-Value insulating? Many high-performance buildings, when addressing the issue of super-insulation, will opt for traditional 2×6 stud framing with an added layer of exterior insulation to help reach……
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…
Energy efficiency of windows: the Uf value
After covering thermal transmittance U and resistance R of opaque assemblies, and insulated glass, we now cover one of the most critical areas of the thermal envelope: window frames. Good windows are the cornerstone of a performing building for both…
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…
Insulation materials: discovering the lambda value
The lambda value of a material indicates its ability to transfer heat: this property is therefore very important in the design of highly performing buildings and passive houses. The information commonly available is unfortunately quite confusing: with this article, we'll…
Mold and condensation: if the solution is worse than the problem
We cover here two real examples of mold and condensation problems, with thermal insulation installed on the inside of existing masonry walls. In both cases, the solutions were chosen on an empirical basis, and turned out to be worse than…
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……
Airtightness: why is it so important?
With this article, we address one of the most important topics in the field of energy efficiency: the airtightness of the thermal envelope. Whether the building is a new construction or a renovation, its airtightness plays an important role for…
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…
Building Form Factor: The Most Overlooked Driver of Cost and Efficiency
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.