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mpt1123 03-01-2009 06:40 AM

Insulation questions for new detached garage
I'm having a detached garage built. I'll be doing the insulation work after it's built and I want to make sure that the prep work is done properly.

The garage has a small room above with knee walls and no attic. I'd like to have a ridge vent and soffits installed, however, soffits seem to be for homes with attics that allow for air to move thru the soffit and out the ridge vent. I'll be attaching the insulation directly to the the roof trusses, effectively blocking the flow of air to the ridge vent.

Eve vents and a powered attic vent don't seem to be the solution either.

How do people insulate and vent a room over a garage?


Just Bill 03-01-2009 06:56 AM

Insulation should never be installed directly to (under) roof sheathing. It causes condensation that will rot out the sheathing. There are foam baffles that you fasten to the sheathing that allows air flow, with insulation installed over them.

mpt1123 03-01-2009 08:18 AM

Thanks for the help. I think I get it now. Install something like Raft-R-Mate from Corning the entire length of the rafter cavity, then insulate on top of that. This would provide a channel for air to circulate between the soffit and the ridge vent. Nice.

Thanks again,

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