I recently put an interior layer of polycarbonate board on my walls and ceiling to create dead air between the corrugated roof and the new layer. I left a small gap at the roof peak door air to escape but I'm not sure that is a good idea. I also have the soffit vented but I put up foam insulation to block that from venting in the winter. Should I seal up the small gaps around that foam insulation to block any air escaping? I feel like that is an obvious yes in the winter time but do I want the soffit to be able to vent in the summer when it's much hotter? I do have a 24" louvered fan in the gable end that I am planning on hooking up to a to thermostat so that should take care of a lot of the ventilation in the summer. Looking for advice. TLDR Should I seal the roof peak and base with spray foam to completely trap the air between my double layer roof? Is that going to cause problems in warmer months? I live in Maryland btw
by Oleblackthumb
2 Comments
I’m no expert, but for the love of goodness don’t use spray foam anywhere.
Is your goal with the second layer to keep it airtight and therefore warmer? I don’t know that two layers of polycarbonate is really going to provide you any insulating value in the winter even if it is airtight. I guess it depends on what zone you’re in.