European windows vs. North American windows
I have read many blogs and Q&A pages from this web site and I am still somewhat confused about European windows.
First of all, there is the U-window differances because of the differing testing conditions (Europe uses a 0 to 20 degree delta T, while NA uses a -18 to 20 — All degrees C). So should I pretty much ignore the U valuse, if I am looking at the “best” glass and frames? and complare the SHG and VT only? The Optiwin figures (SHG 0.52) seem to beat anything that Thermotech has (SHG 0.42), or is that somehow measured differently in Europe too? Transmittance has to be measured the same?
There is also the installation method. Most NA windows have a nailing flange while European windows seem to be flangeless. There are advantages to both, though. But isn’t it ideal to place the window somewhere midway into the depth of the wall? Don’t you give up insulation value by placing the window out by the siding? Of course, having the window install out that far makes for a much easier finishing process with respect to water plane detailing. European windows, if set into the wall, would require more thought, but you also get to wrap a little foam up to the frame (I suppose this could be done inside and outside), which seems like a good idea, albeit somewhat time sonsuming.
Do I have this right? Are there other considerations?
As for costs, I have seen figures all over the place on this web site. That might have to do with the various dates over which the numbers were posted. Can folks that are using the latest amd greatest window technologies post current relative quotes that they have received for their projects?
I like the idea of Figerglass windows. I hate PVC and wood is OK, if that is what I have to go to to get a superior frame. I cannot find any European Fiberglass window makers. Is there a reason for this?
FYI I am looking into a Passive House build for retirement, probably in zone 5