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Community and Q&A

Dudley Box vs. Plywood Buck

JZohio | Posted in General Questions on

Hello I am in the process of redoing a portion of my house and while the siding is off I want to address the windows. I have removed the layers of old siding, attached 1.5 inch polyiso (zone 5) and installed tyvek over top. There are two year old vinyl replacement windows in a homemade buck from many years ago that is going to be removed. I plan on reusing the vinyl replacment windows and installed masonry clips to the jack studs as listed in the articles. I’ve gone thru so many and I’m still left with a few questions. I plan on installing vinyl siding when finished. With the plywood buck I would then only extend to the edge of the foam and stop right? In the other articles I am to go out 3/4 of an inch to allow for the vertical furring strips. Is this needed in my case? If I flash these as outie windows with a plywood buck, would it be necessary to install the vertical strips? Would dudley boxes be a better choice? Thanks

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  1. brian_wiley | | #1

    My understanding is that vinyl (and metal siding that emulates lapped siding) doesn’t need an air gap provided by 3/4” strips as their assembly lends enough air circulation.

    Hopefully one of the more experienced members can address the question of buck vs Dudley box relative to the order of your sheathing/foam/wrb.

  2. GBA Editor
    Kiley Jacques | | #2

    It sounds like you’ve done a lot of reading already, but if you decide to go the Dudley box route, be sure to check out this Fine Homebuilding article: Fitting New Windows in a Crooked Old House.

    1. JZohio | | #3

      Page does not exist

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