Sound-Proofing Office Walls

Is your office in the same building as a shop full of noisy equipment? Here are a few tips on how to keep noise out of your thinking space. October 1, 2005

I am moving to a new shop and have to build a new office. My last office was 2x4 framing insulated walls and ceiling and I can still hear shop noise. Does anybody have any tips for making my next office quieter?

Forum Responses
(Cabinetmaking Forum)
From contributor J:
You can go 2 x 6 insulate, with double 5/8 firecode rock. You can also use inner layer of homosote, then sheetrock. I would suggest using rigid foam instead of glass.

From contributor B:
One of the best ways to sound proof in that situation is to build two walls (can be 2x4) separated by a small gap (1"). A second thing to do is to put a lot of mass on the wall between you and the sound - 5/8 sheetrock is a pretty good option. Hang that on both walls of a double wall, and it should cut a lot of the noise.

One way to think about noise/sound is that it's simply vibration. So, whatever you can do to prevent something from vibrating (transmitting sound) will be good soundproofing. That's why a lot of mass is good.

If your shop is on a concrete pad, another option would be to build the office walls out of cement block. That would provide plenty of mass. It would be even better if you fill the holes with concrete. The other thing you need to watch for with soundproofing is air gaps. Any little space that air can pass around or under doors, over the top of the wall, etc, will transmit noise.

From contributor W:

Contributor B's point about using two walls with a space between is a good one. I would suggest that instead of a hollow space, use a sheetgoods material called soundboard. It should be available from a company specializing in acoustical materials. This board is specially designed for just this purpose. The supplier may even have more details to offer you on how to soundproof.

From contributor T:
I would suggest using 2x6 top and bottom and 2x4 studs every 8" alternating flush to each side of the 2x6. That's how you get your wall separation so most vibration on one wall won't go through to the other. Use soundboard under the sheetrock on each side. I've heard that filling the wall with sand will stop a lot of the noise too.

From contributor R:
Any glass should be insulated with 2 pieces of 1/4" laminated, set in with 3/8" double stick glazing tape to stops/jamb. The laminated glass really dampens the sound. Go with two units if you want any noise at all.

From contributor R:
Contributor J knows what he's talking about on the homosote. It's a cellulos sheetgood that’s made by Weherhouser – it’s pricy but stops sound. Cellulos insulation in the walls would be good to.

From contributor F:
If you have ever been in a musicians practice room and seen egg cartons covering the walls, that is the same stuff homosote is made from. I have occasion to see a few recording studios and, as far as glass is concerned, they always leave about .5" between the two panes.

From contributor F:
I agree with the idea of building two walls. Make sure you alternate the studs or the noise will travel through the soundboard and through the second stud. It will be somewhat deadened by the soundboard but it will still get to the other side.

The comments below were added after this Forum discussion was archived as a Knowledge Base article (add your comment).

Comment from contributor A:
I'm a radio engineer and have built my share of sound proof rooms. I would recommend that on wall studs you saw all the way through the wide side of the stud - 4" side of a 2x4 or the 6" side of a 2x6 almost the full length of the stud. Leave the last 5" on both ends un-sawn for attaching to the top and bottom plates. This will vastly reduce vibration (sound) transfer from one side of the wall through and to the other side. Use homosote strips between the bottom and top plate and the floor and ceiling.

You can also buy sheet lead to put between the studs and your final sheet rock although it's very expensive. There are some synthetic sheet materials that can be used instead of lead, but they too are expensive. Finally this may sound silly but believe it or not sound will travel through the smallest of holes and cracks so be sure to caulk every small opening you can find.