Enclosing a Porch for Conditioned Space
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I would like to make an existing bedroom larger by enclosing an adjacent entrance porch that is 7′ x 9′. The deck of the porch is an 8″ thick concrete slab with a basement below. The joists that would be above this deck need to be 2×6’s.
My concern about doing this is that the deck would have two edges covered only with 1/2″ ply and vertical cedar siding.
Would it be sufficient to use closed cell spray foam in the joist bays to insulate this space?
Removing the deck would be a monstrous task which I would rather avoid. Any thoughts would be appreciated.
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