Is it OK to put rigid foam on two sides of cellulose in a sloped roof?
We are planning to insulate at the roof for a shed portion of our home. We are planning on using densepak cellulose in the 2×12 rafter bays with a ventilation chute at the top. We would like to also add 2″ of rigid at the underside of the rafters to reduce thermal bridging and bring the R-value up for the assembly. I believe that I have heard the technique of using rigid insulation to create the ventilation chute at the top of the rafter bays, which would help us as we try and reach an R-49 for this assembly; But is it a mistake to have the rigid on both sides of the cellulose?…
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