Does exterior rigid foam require plywood box around window framing?
We’re renovating a 1950s home in Massachusetts. The home is constructed of 2X4 framing with pine sheathing wrapped in tar paper and sided with cedar shingles. I’d like to increase the r-value of the home by replacing the cedar shingles and tar paper with a peel and stick membrane, 2″ pink rigid foam, furring strips and HardiePlank lap siding. Harvey slimline windows will also be installed.
I understand the thickness of the wall will grow to about 7-8″ deep. When creating window framing details I’m thinking we should position the windows towards the center of the wall. Should the outer perimeter of the window jamb be framed with plywood to seal and provide a firm area for the window to sit?
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