I’m converting a 1910 carriage house to living space and I’m trying to decide how to insulate the hip roof. Pics attached. I was thinking closed cell spray foam because of the difficuly venting otherwise. Any ideas?
I’m converting a 1910 carriage house to living space and I’m trying to decide how to insulate the hip roof. Pics attached. I was thinking closed cell spray foam because of the difficuly venting otherwise. Any ideas?
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Replies
Given the condition of the wood and age, I wouldn't consider spending money on sprayed in place foam.
That roof structure looks like it will be due for a major replacement soon and sealing it would only accelerate the detoriation process.
Gabe
steve... gabe's got a good point...
the framing looks ok.. the roof boards have a lot of broken ones... the framing is light , looks like rough 2x6.. so not much depth for ventilation and insulation...
i think i would strip the roof, overlay with plywood and renew the exterior trim.. when that was tight and right..
i'd nail 2" eps to the bottom of the rafters.. and then furr it ... then i'd blow dens-pak cells into the cavity and create a cold roof with no ventilation..
2" eps = R10 ( and a good thermal break ) and 6" cells = R21.. for a nominal R30..
but i wouldn't do any of this until i had a new 30 year roof on it with plywood overlayMike Smith Rhode Island : Design / Build / Repair / Restore
Mike,
I'm surprised you did not recommend the Mooney wall.
1.5 furring over the rafters would yeild R5.1, as opposed to the R8 for the 2" EPS, so a small loss there, but you are already planning on bringing the cell blower to the site to fill the cavity, why not fur, mesh, and blow the whole thing?
In fact, to mimic the RFB idea more closely, you could nail 2x2's to the rafters and fur on top of them. This would give you R10, with only 1/4" lost headroom vs. the EPS.
Jon Blakemore
excellent idea ! and elegant too !.... long as he reroofs firstMike Smith Rhode Island : Design / Build / Repair / Restore