Choosing High-Performance Windows
Finally moving forward on a zone 7 house build in Northern Wisconsin this spring and I need to settle on our window selection.
The house is 2,000 sf and we’re using a 2×6 dense pack cellulose wall with 4″ of mineral wool exterior insulation. We’ll have a combination of deep insulation in attic truss and 18″ vented i-joists for our roof system. We have not yet completed a REScheck or WUFI analysis but for the sake of the completion of our architectural drawings, I need to settle on our window package ASAP.
We’re after an aluminum-clad wood window for aesthetic and durability.
I’ve received quotes from countless companies but considering the product and service, we’ve narrowed it down to 2–Loewen and Zola. Here is the info:
Doug fir casements and fixed
Total window and door cost: $43,873
Airtightness: .03 cfm/ft2 @ 1920 Pa (40.10 psf)
u-value: 0.2 operable, 0.17 fixed
Finger-jointed pine tilt-and-turns (can upgrade to other woods)
Total window and door cost: $45,527 + $5,800 shipping = $51,327
Airtightness: .03 cfm/ft2 @ 4,800 Pa (100.25 psf)
u-value: 0.16 operable, 0.16 fixed
Seeing the samples, I expected the Zola performance to be quite a bit better than the Loewen package as they were much more robust. As far as my knowledge goes, Zola is only modestly better u-value and the same airtightness (though different design pressures) as listed here. Am I missing something?
Can anyone provide more insight on how these windows and doors compare? Zola is $7,454 more when you include the additional shipping cost and another $5,000 if I were to upgrade to douglas fir (like the Loewens).
How will these windows compare and perform in real life?
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