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Community and Q&A

Rockwool on Backorder

the74impala | Posted in General Questions on

I have finally landed on my cathedral ceiling system. I have site built plywood 1 1/2″ baffles,  air sealed, R30 Rockwool, R15 Rockwool (both 24″ o/c), Intello, 2×4’s on edge perpendicular to rafters with R15 on 16o/c with drywall /T&G ceiling. 

My problem is the R15 24 o/c is on backorder until the end of December.  How much trouble would I cause by putting up the R30 and waiting a month until I air seal after the R15 24 o/c finally gets to me?  I would love to turn on the heat above 40°F soon and hopefully slow ice dam accumulation. 


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  1. Patrick_OSullivan | | #1

    If time is of the essence, why not just get some R-15 fiberglass and call it a day?

  2. the74impala | | #2

    Holding it up there at a 45° angle until I can get the Intello up does not sound like fun.

  3. the74impala | | #3

    How much moisture is going to get trapped? I have plywood as the baffle. Would that much moisture get trapped behind the R30 when it is open into the house and has an air channel above it?

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