Basement Soundproofing

June 21, 2004 6:58 PM

So, our noisy basement suite tenants have moved out, and before new ones move in, I'd like to do a little soundproofing. I've found a fair amount of material on the web, (like this, this, etc.) but they're all trying to sell me something, which doesn't exactly inspire confidence. Our house has original hardwood flooring, so carpeting/underlay is out. Any tips to cut down on voice, music, and "intimate" noise transmission from people who've done this before?

I'm thinking of adding some kind of material to the ceiling below, and covering it and painting it with another layer of drywall. Just not sure of what kind of material to use...

posted by kaefer to Home & Garden (7 answers total)

the most important thing in sound proofing a floor is having a section of air that allows the sound to be absorbed. may I suggest 2" of rigid insulation, 1/2" strapping or steel studs on their sides and then two layers of 5/8" gypsum (drywall) with staggered joints to really do the job? of course this will only be as good as any insulation around the beams and columns that can transmit vibration, but you should notice a difference. You should check the sound transmission classification on different ceiling assemblies here: USG Construction Handbook.
posted by grimley at 7:19 PM on June 21, 2004

It's obviously to early to suggest this, but eventually Aerogel might become cheap enough to use as acoustic and thermal insulation. I wonder if something similar (albeit less advanced) is available today?
posted by SPrintF at 8:30 PM on June 21, 2004

Cork. Trust me, it works. Line the downstairs ceiling with cork, then drywall over the top.

If it could dampen down the sound of my brother's band, it can dampen the sound of anything.
posted by anastasiav at 9:18 PM on June 21, 2004

Staggered joists. Of course. And mineral wool insulation... but beware: mwi is heavy, and needs solid support.

If you're not sure what staggered joists are, check out the figures in this PDF.
posted by silusGROK at 10:46 PM on June 21, 2004

There are, as I recall, some serious fire code issues with potential soundproofing materials, so I'd make sure whatever you do meets code - failing that, at least be aware of the code, so you're cognizant of any risks you may be taking.
posted by jalexei at 5:57 AM on June 22, 2004

This Apartment Therapy entry talks about soundproofing and provides a couple of links...
posted by sad_otter at 8:37 AM on June 22, 2004

Fine woodworking from Taunton press had an article about soundproofing a basement shop late last year. If you can silence a tablesaw, you can silence anything.
posted by jmgorman at 10:11 AM on June 22, 2004