Window debate
I am getting ready to order my windows for my new build in central maine and am debating between cost and performance. The two windows I am debating are Mathews Brothers Sanford Hills and Mathews Brothers Spencer Walcott.
I need 18 windows and 2 sliders:
Sanford Hills =$19,700 Air Infiltration =.01, U factor =.26, SHGC =.28
Spencer Walcott =$13,000 Air Infiltration =.11, U factor =.28, SHGC =.31
is it worth the extra $$ for the improved AI number? I was reading some articles that say you start to get to the region of diminishing returns below .1. On the other hand a .1 cfm/ft2 difference across 18 windows equates to 3-5 cfm across the whole house.
thanks,
steve
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Replies
From a comfort point of view spend the extra and buy the better window assuming you can fit them in your budget.
If this is about return on investment then the only real way to get an answer is to spend 30 hours of your time learning and entering the cost per square foot of each window into a computer model of your house with your weather data and fuel costs.
https://www.youtube.com/playlist?list=PLHC0xDtkdjgec8QhVt7exJY3tpSLEFk-d
https://www.nrel.gov/buildings/beopt.html
Walta
Yes, but honestly before you pull the trigger. I'd get a quote from a company like Alpen High Performance Products. 2x+ performance, better warranty, their Tyrol window has virtually 0 leakage 0.01% to 0.03% for operational, and said to have a similar price to conventional windows. Made in America to boot.
I installed Spencer Wolcott casements in my kitchen and they have performed well for nine years now. They're only double glazed but on many mornings there is condensation on the exterior, which is annoying but a sign they are performing reasonably well since they face north.
We're about to install Sanford Hills triple glazed windows on the second home I've designed for clients. They are triple glazed so lower U-factor is closer to 0.20. They are very affordable so unless your budget is extremely tight--as mine was when I installed the Spenser Wolcott windows--I would go with triple-glazed Sanford Hills. They will pay for themselves in energy savings eventually, and you'll be more comfortable for the entire time. I don't see any sense in spending $7K for an improvement of U-o.02, though. And I don't have any experience with their doors.