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Community and Q&A

Quick and dirty tongue and groove air seal

BILL WICHERS | Posted in Energy Efficiency and Durability on

I have a small area, about 10×12 feet, with a tongue and groove ceiling. The attic space above it is inaccessible, and insulated with batts laid over the t&g. There is no air barrier and wintertime frost on the roof shows this to be a leaky area.

I’m looking for a quick way to air seal the ceiling without disassembly and I’m thinking of applying a few heavy coats of polyurethane (it’s a stained ceiling) and then some canned foam around the edges prior to putting up some crown moulding. This only has to last a few years until we renovate that space.

Any thoughts?


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  1. walta100 | | #1

    If you want to air seal the tong and groove with polyurethane.
    Apply copious amounts from to the top only when you have applied enough layers that puddles of poly will not drip thru will it be air sealed.

    This will not be quick, ease or cheap but it will be very dirty.


  2. user-2310254 | | #2

    Is the air leakage severe enough to warrant immediate action? If not, why not leave things as-is until you can properly renovate the ceiling?

    1. Expert Member
      BILL WICHERS | | #3

      It’s probably a pretty big amount of air exfiltration, but I haven’t actually measured it — I have two nearly identical parts of the house, one drywalled and the other with the t&g ceiling. Frost patterns show a very significant difference.

      I already have enough polyurethane to give it a try, and it’s relatively quick and easy to apply. I’m thinking it will give at least as good a seal as painting the ceiling would. The future renovation plan is to vault the ceiling and spray foam it, which was done this past year for a low-slope ceiling and it worked very well.


  3. brendanalbano | | #4

    Here's a silly and perhaps terrible idea: Plasti Dip it!

    Make sure to pick a fun color!

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