Author Topic: Soundproofing panned joist return?  (Read 7919 times)


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Soundproofing panned joist return?
« on: December 03, 2015, 02:40:57 PM »
We have a cold air return that goes from the first floor to the basement through a panned joist (just a piece of sheet metal nailed over two joists). There are loud birds on the first floor, and we are trying to stop the sound coming down from the air return into the basement. What would be the best approach?

I was thinking of loosely covering the two joists with MLV / acoustical barrier from below. Would that work? Or should I put some sort of foam insulation over the duct first, then put the MLV over that? Any other ideas?


Randy S

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Re: Soundproofing panned joist return?
« Reply #1 on: December 03, 2015, 04:17:57 PM »
Line the entire cavity with our foam mat, at least 1/2" thick and the pan.

before putting the metal with foam back up you want to put a few blocks of foam glued in creating a series of 90* turns.

You are making a baffle box.

when the metal goes back up you can cap it with 1/2" hardie backer cement board.

feel free to call me direct if you have questions.

Randy S.
Randy Sieg

Super Soundproofing Co
Ph. 760-752-3030


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Re: Soundproofing panned joist return?
« Reply #2 on: December 03, 2015, 04:31:22 PM »
This is great information, thank you!