Sound Proofing Drywall

tigas

I used ½ Quiet Rock Drywall as recommended by the company on a wall between two apt. units. The QR drywall was installed by drywall installers per product instructions over the original wall. Which was drywall covered with ¼ plaster on wood 2x4 studs. The building was constructed in 1968. I can still hear people talking, and tv, on my side of the wall where the QR was installed. The sound has been reduced, but at $45.per sheet plus installation I am not happy with the results. Would blowing insulation into the wall cavity stop sound?

woodworkerjeff

I don't have a ton of experience with this, but here's what I know.

I'm sure blow in insulation would help..but just like the drywall I doubt it will completely stop sound..especially since the walls are 2x4. 2x6 walls give more room for blow in insulation. And you don't want to pack the insulation tight. Tighly packed insulation can actually help tranfer sound through vibrations. I would also wonder about the floor and ceiling framing. Sound can travel through the cavities between those joists as well.

tigas

the building sits on a concrete slab, and it is a one story with a crawl space/attic above. Isulation is blown in to the attic to the top of the rafters. the sound is coming from the wall.

rightit

Blowing insulation in would have minimal effect, and may make things worse. You say the QR was installed 'as per instructions', but there is a lot of detail to cover, and unless your drywallers understood the issues involved and how to address them, you may still hear noise.

Your problem may be 'flanking' noise. That is, noise that goes around the QR via unsealed openings. For instance, it may be traveling through the joist space on top of the wall, or perhaps acoustic sound sealant wasn't used around the perimiter of the QR, including at the floor, under the QR.

There are lots of ways noise can 'leak'. I've done extensive research on soundproofing for an in-process project. I thought about using QR, but decided on a staggered wall with 2 layers of 5/8" rock and GreenGlue, as it was a bit cheaper. I hear that QR is good, though, but it must be properly installed, which means addressing all ways that noise can enter (think of noise as water. If there are leaks, it will 'seep' through).

Here are some links I've saved. Really good info at both of these sites:

GG's technical library along with 2 very interesting articles (included in the 1st link as well):

http://www.greengluecompany.com/technicallibrary.php

http://www.greengluecompany.com/unde...nkingNoise.php

http://www.greengluecompany.com/five...ndproofing.php


Very informative here:

http://www.greengluecompany.com/five...ndproofing.php

And:

http://www.soundproofingcompany.com/library/articles/

http://www.soundproofingcompany.com/...cles/flanking/

Read through these and other articles in the libraries before you spend any more money on it. Be fully educated so that you know what needs to be done, how much it will cost and how it will perform.


Mark

vsheetz

During a whole house remodel year before last I built a staggered stud wall between living room area (with TV) and master bedroom. My wife usually goes to bed before I do - has kept her happy.

http://www.diy-home-theater-design.c...stud-wall.html

pyper

Are there outlets in the wall? Sound will go through those.

woodworkerjeff

Learned something new today..great design..thanks!!

rwfifty

my experience has been that no matter what you put in the wall cavities you will still get sound travelling through the wood studs (great conductor). We solved our apartment problems using Roxull Safe and Sound insulation and by sheathing the wall with fibre board (used for exterior wall sheathing) before applying the drywall. Nothing stops some neighbours noise though.