Separating wall insulation from ceiling insulation
Corey867
| Posted in General Questions on
I have an atypical wall setup. My rafters sit directly on top of my studs and I have no top plate. I am doing a renovation to add additional framing and to add insulation. The setup of my home prevents me from making these “normal” framed walls. My understanding is that I need to isolate the wall insulation from the ceiling insulation with an air impermeable barrier. (The ceiling is cathedral-type.) Is my understanding correct or could the wall and ceiling insulation be “continuous”?
Thanks.
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Replies
Corey867,
As long as your cathedral ceiling has an air-barrier above the insulation you are fine with the two being continuous. If not you will want to add blocking between the studs at the top and air-seal it.
Thanks Malcolm. Could you clarify this a bit? Currently I have "canvas sheathing" on top of my rafters forming the ceiling and roof. (I live in a yurt.) This is relatively impermeable. Is this what you consider an air barrier? When I eventually insulate the ceiling I am planning on adding a vapor retarder to the inner face of the rafters but I am planning on a contingency where I may only get to insulate the walls this year and will have to wait to do the ceiling.
Thanks.
Corey867,
Then you should probably try and seal between the two. Otherwise you will get convective air currents drawing air up the walls and out the roof, which will diminish the effectiveness of your wall insulation.