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Community and Q&A

What makes a “good” window?

jcastilow | Posted in Energy Efficiency and Durability on

Aesthetics aside, I’m wondering what qualifies as a good window from a thermal efficiency and durability standpoint.

In this thread:

Martin himself calculates that the cost difference PER YEAR PER WINDOW for a u-value of 0.2 vs 0.3 is around $1-2 – see thread for specifics.

I’m looking at Atrium’s Reliabilt windows series which have a u-value of 0.27 and a SHGC of around 0.2 (paper not with me right now) vs. a Pella 250 series with a u-value of 0.2 and similar SHGC. Both low-E and argon filled. Both limited lifetime warranty. Yet, a price difference of nearly $250 ($300 vs $550, respectively).

Had a guy out to quote installation, and he said he didn’t think Reliabilt were “good” windows but liked Pella.

So, I’m asking the GBA community: what qualifies as a good window? Thanks for the help.

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  1. PAUL KUENN | | #1

    First I want to know about the trustworthiness of the Rep, so many Reps don't have a clue and I frankly don't know how they got the job. Next, is the frame Durable? If going with less expensive vinyl, then I want it to be insulated (foam filled) as I'm in zone 5-6. Spacers between glazing need to be non conductive. Also, I require a U-factor of .18 or less as I don't want clients mopping up moisture from a cold window when they're cooking pasta. Then, I ask the GBA crowd the scoop on brand names. You will get plenty of helpful replies.

  2. Expert Member
    NICK KEENAN | | #2

    A good window is durable. That means its performance 10, 20 years down the road doesn't suffer because the seals have failed and the argon is gone. It means it doesn't get chucked in a landfill because the frame is rotted or the glazing fogs up. Or the handles have broken and can't be replaced.

    Glass generally lasts a long time, although it might haze or get scratched. But generally windows get replaced because something other than the glass has failed. Carting a window off to the landfill is not green.

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