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Fasteners and Sealant for Window Installation

Ryan_SLC | Posted in General Questions on

Hey all,

I am almost done with my rookie window questions. I do have two final questions where experts know the answer but this rookie is left missing the most basic knowledge.

Re: window w/nail flange: what scew/nail and what “good sealant caulk”?

My mix of Anderson and Simonton new construction nail flange windows call for good silicon sealant and a quality screws. Simonton calls for nails, “Use a corrosion-resistant fastener with a minimum head size of 5/16” or larger that will penetrate a structural framing member at least 1”

I thought nails were out as a good idea because of vibration from the hammer and worst case, a strike to the window?

What exact product do people like to use here?

Thank you!

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  1. Expert Member


    I use a pancake head metal roofing screw.

    1. Ryan_SLC | | #2

      had a laugh. I haven't heard of "pancake"!

      2 inch?

      Thank you! Obviouse looking at "pancake" that this solves the problem of the protrusion from a common pan head causing trim to protrude? Nice.

  2. Patrick_OSullivan | | #3

    GRK cabinet screws.

    I think sealant under the flange is a mess waiting to happen and not really useful when you are properly taping the flange and air sealing the inside.

    1. Ryan_SLC | | #4

      GRK is sure weird about if these are exterior or not. Says they are coated and pressure treated approved...but nowhere says exterior use?

      1. Patrick_OSullivan | | #7

        From "GRK products are Climatek™ coated, approved for use in treated lumber, and designed for both interior and exterior use."

    2. steve41 | | #5

      +1 - GRK cab screws and no sealant under flange, assuming diligent taping

      Side note: the spec I reviewed stated indoor / outdoor use

      1. Ryan_SLC | | #6

        It's possible. I'm looking on homedepot and the box and specs don't mention exterior at all, just the "Climatek coating is AC257 code approved for use in treated lumber" which can infer exterior, but then the comments say no.

  3. Ryan_SLC | | #8

    I just wanted to update that I bought the GRK cabinet screws at homedepot.

    You all were 100% right. The box does say for exterior use, it's just on the back. So the online HD description and questions/reviews were wrong.

    Thanks all for heading me in this direction.

    Take care.

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