Window buck material options?
Hey all,
I was planning on using a 2x material to buck out my windows to accommodate the exterior insulation. However, from looking at some of the lumber on-site, available at the local big-box and at the lumber yard; it seems like getting something installed plumb and flat that doesn’t warp too much may be difficult. I have seen the foam-style bucking material, but I don’t like that so much as the screws have to go in a weird angles to get a good purchase in wood.
I am considering OSB and plywood, but that would mean nailing into the edges and I don’t know if that is a good idea.
Do you guys have any suggestion for a material that is more likely to stay flat/plumb when installed?
Would it be okay to use layers of plywood and fasten the window screws into the edges ‘grain’?
thanks.
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Replies
I wouldn't fasten into the edge grain of sheet goods; they will split and won't hold well. But you could rip two strips of 3/4"x3" plywood and run that around your openings on the flat, so you would be fastening into face grain.
Michael - do you mean on the flat with the end grains of the plywood behind as in the picture attached?
I usually face nail the bucks to the sheathing (they don't go into the rough opening at all). This avoids any of the flatness issues, regular 2x lumber ripped to foam thickness works great.
Sometimes for larger doors, you do need more support in that case use LVLs for the bucks. These would extend inside the rough opening and be nailed to the studs for support.