Vapor Control With LP SmartSide Panels
atmanseer| Posted inGeneral Questionson
I have a large shed which will be converted to a shop studio. It is sided with primed and painted thin (approx 3/8″) LP smartside panels as siding and sheathing. I can’t get a straight answer as to if the panels are considered impermeable and I will have to plan for drying to the interior or if they will dry exteriorly. There is a permeable house wrap between the panels and the studs. Can I use rigid foam for insulation between the studs using “cut and cobble ” technique? what type of rigid foam is permeable enough to will allow drying to the interior. Or do I need to go with fiberglass batts or cellulose to allow drying in that direction?thanks
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What is your climate zone?
"Wood, vinyl, and composite siding aren’t reservoir claddings, making inward vapor drive less important, but a drainage space or material prevents moisture accumulation behind the siding and helps protect the wall, even if not required by code. Note that some sidings may not qualify as a vented cladding without a back-vented air space." --Take a look at the attached resource.
Thank you for your response and the article. I'm in Climate Zone 6. Don't want to create a double vapor barrier, so wondering if the smartsiding panels are impermeable enough to act in that way if combined with rigid air-sealed foam used in the stud cavities as insulation. If the panels are more permeable then I have less apprehension about using the foam.