Is a vapor retarder necessary on ceiling/attic interfaces of unconditioned attics when using blown in cellulose or fiberglass insulation?
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Hi,
I’ll start this out by saying I might be overthinking this …….
My goal is to prevent condensation on the plywood sheathing of our unconditioned attic that could result in attic mold growth – especially during heating season during our cold climate zone 5 winters where temperatures can get as low as 0 degrees Fahrenheit at times.
Question: Is a vapor retarder needed on ceiling/unconditioned attic interfaces when using blown in cellulose or fiberglass insulation of sufficient R value; and if this is the case, is latex paint sufficient (assuming all of the other areas for air leaks have been air sealed?)
Thank you for your time.
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Replies
mclola,
https://www.greenbuildingadvisor.com/question/vented-attic-vapor-retarder
Thank you for this link/information, Malcolm.