Rigid foam and rafter tails
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The attic is conditioned space due to foam spray on the underside of the roof deck. Foam also fills the void between top of wall and roof deck. So, when I install my exterior rigid foam should I stop at the top of the wall or cut out for rafter tails and continue the foam to the bottom of the roof deck.
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Replies
Robert,
Either way will work. If you take the latter approach, the blocking between your rafters or trusses will have a higher R-value, and the rate of heat loss will be reduced.