# Seeking Insulation Advice



## Windows on Wash (Aug 30, 2011)

Rigid foam would work best. 

Spray foam and seal all the gaps prior to installing it and you will need to cover it (or it will need to be foil faced) with a code approved thermal/ignition barrier.


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## Jim Ignatowski (Dec 20, 2011)

Thanks for the reply. Can I ask how you suggest I secure it to the wood, I think I would either need to nail it (which I prefer not to do) or use some kind of an adhesive. I've used locktite with foam board before but that was against concrete. Also, is there a foam board product that has the thermal/ignition barrier included? Thanks again


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## DexterII (Jul 14, 2010)

I am going to respectfully resign to WOW's advice to you, because he's good at this, but wondering how much work it would be to remove the plywood and fill the wall cavity, rather than going over it. Seems like that would seal it up better, and would also address cold coming through the bottom plate. Also, are the rafter bays above the room insulated?


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## Windows on Wash (Aug 30, 2011)

Dexter,

That is a good catch. If that's the cavity does not have insulation and it it does need to be filled. The point of the rigid foam is that it helps with the thermal bridging of the framing assembly and rigid foam is also very stable and does not suffer from wind washing degradation.


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## Jim Ignatowski (Dec 20, 2011)

I've confirmed the walls of the room (behind the plywood have fiber glass insulation. Also the ceiling above the room is the upper attic which has spray foam insulation. I think the issue is that behind that plywood is a heating convector, and that cavity is not insulated and that's where most of the air leakage is. The plywood on the left is the bottom portion of the exterior wall ... The upper portion has two windows and looks over the porch roof. thank you.


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## Gary in WA (Mar 11, 2009)

IMHO, the roof is your biggest thermal loss, exposed to the elements above and outside temperature air on the attic side- tied to the wall with no thermal break. Insulate the rafters (and ends of the floor joists) close to the wall to slow conductive heat loss, similar to an exterior patio balcony; http://www.buildingscience.com/documents/insights/bsi062-thermal-bridges-redux FB over the ply, caulk ALL joints of framing (incl. joists), sheathing as suggested is very good.... Gary


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