Why is there no plywood sheathing shown in your window installation construction details?
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Hi all,
I was looking through the “How to Install Windows Right: Details for Leak-Free Windows and Siding” and didn’t see plywood or OSB sheathing under the rigid foam sheathing in the drawings. What am I missing?
Thanks in advance,
Cecily Feudo
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Replies
Cecily,
If you are building a house, you can choose to install whatever type of sheathing you want. You can choose plywood sheathing, OSB sheathing, or rigid foam sheathing.
Many builders choose to install rigid foam sheathing on the exterior side of plywood or OSB sheathing. But it isn't necessary to have both plywood and rigid foam. You can have just one of these two layers if you want.
If you decide to use rigid foam sheathing without any plywood or OSB, you'll need to be sure that you have a good plan for bracing your walls. Here is a link to an article that explains all of the options: Four Options for Shear Bracing Foam-Sheathed Walls.