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What are the best basement windows?

user-6474580 | Posted in General Questions on

We have three standard size basement windows to replace. I was looking at the hopper windows. Any other recommendations? Thx in advance!

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  1. GBA Editor
    Martin Holladay | | #1

    Masb H,
    Everyone has opinions. A lot of people just install vinyl-framed hopper windows.

    If this is finished space, it's usually best to have at least one egress window. (This usually requires a special type of window well with stout retaining walls.)

    If this is an ordinary unfinished basement, my own preference is to fill the old window openings with bricks, concrete blocks, or poured concrete. Unfinished basements don't need windows.

  2. Expert Member
    Dana Dorsett | | #2

    Some local codes demand some minimum amount of operable window area even in unfinished basements, the rationale being minimal daylighting for safety when the power is out, and for drying/venting after chemical or paint spills, floods/plumbing leaks etc.

    Those codes can sometimes be negotiated with the inspectors. I know of one project where they got a variance to allow insulated glass block instead of operable windows, which preserves daylighting with better air tightness than an operable window. But from U-factor point of view it was still pretty crummy- factoring in the thermally bridging mortar glass block typically comes in around U0.50. A non-operable low-E sealed glass window would have had higher performance, but would have been (a lot) more expensive.

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