Spray foam under outdoor space. Good or bad idea?
I’ve got a outdoor patio, about 300sq/ft. Its got a hallway on one side, and covered patio on the other.
The hallway already has sprayfoam on the underside of the roof deck, in the wall cavity and under the slab. Its represented by area in blue (see attached).
The covered patio area currently has nothing for insulation in it. I was planning on doing T&G fir on the underside of the covered patio under the vault.
I’m wondering if there is any benefit to putting spray foam or any insulation under the covered patio even though the area is not heated?
Should I be venting the soffit area? Do I need any roof vents?
It goes from -40C in the winter to +40C in the summer. I’m located in Northern Alberta.
I’m looking to prevent mold or deterioration of the sheathing under the covered deck.
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