Is there thermal bridging in the Edelweiss REMOTE wall?
In the Edelweiss home, it is said that two layers of strapping prevent thermal bridging. Albeit, the screws from the second layer of strapping do not go directly into the studs, but they still go directly into the first layer of strapping which is itself directly screwed into the studs. So there is still some thermal bridging. Did the software analysis however prove that this indirect degree of thermal bridging is so elongated (from outer screw through inner strapping to inner screw to stud) that its net effect it so greatly reduced as to be neglible?
Yes, exactly. Since the screws do not go right through the wall assembly, the thermal bridging is drastically reduced. There are other attachment systems, such as the fiberglass Cascadia Clips that also reduce the thermal bridging to being negligable. The double strapping system is similar in effect, we just chose that system to keep it fairly normal looking in the eyes of builders, since we were pushing the evelope a bit in terms of what people were used to seing.
Only in a windowless and doorless building with a complete seamless insulation envelope would you completely eliminate any thermal bridging and have a perfectly balanced R value over the entire envelope with no weak points. But that would be a sad house to live in : (
And difficult to enter with no door :) Short of that, it’s a case of doing whatever you can to limit heat loss.