A friend of mine had a similar noise complaint in his party wall. He built a wall in front of the problem wall and had an insulation contractor spray a closed cell polyurethane spray foam into the new wall and he says he can't hear a thing thru the wall since the foam was installed.

Posted by: BMarch267 at May 3, 2008 6:06 PM in response to Party wall soundproofing

closed cell spray-in foam is GREAT for deadening sound. not as great for impact noise however, but that's probably not the issue here.

Posted by: guest at May 3, 2008 8:42 PM in response to Party wall soundproofing

So many answers to questions can be found by reading an old Journal for Light Construction article that can be found at http://www.soundsense.com/pdfs/Schnitta-JLC-0206.pdf.

For example -
1. Insulation does not stop sound, it absorbs, BUT blow in insulation will fill holes. This is important since a 1" hole will negate most of whatever soundproofing you have performed.
2. The one inch hole is why Quiet Rock fails. This article mentions an alternate product, SoundSense LV-1. This product is like 3+ layers of sheetrock.
3. The best party wall would be the previously described double wall with SoundSense LV-1, or NoiseOut 2 (when there is amplified sound). If there is not enough space for the double wall, the clips described in the article with LV-1 or NoiseOut 2 will work equally well.
4. Make certain any electrical outlet is acoustically wrapped.
5. Caulking is critical (remember the 1" hole).
6. See the article for additional help.

This product was also highlighted in an article by Myron Ferguson ("That Drywall Guy") in Fine Homebuilding.

Posted by: guest at May 4, 2008 12:09 AM in response to Party wall soundproofing

Good info, 12:09. We might soundproof a wall in our house that way eventually, but sadly it's the smallest bedroom in the house so we'd lose another 6 inches of width in the room.

2:33 we have a loud music issue next door and in trying to work with the homeowner we learned that his house had very little rugs anywhere, and his speakers were sitting either directly on the floors or were in a boombox on a piece of furniture that was sending the sound directly into the floor. As some are describing, the noise is traveling between shared joists in the floors and the back wall of our houses.

Try putting a rug and sound absorbing pad underneath the shelf or table you have your stereo unit sitting on. And don't rest that piece of furniture directly against the wall. Ask your neighbor how it sounds then. You should get on the phone with her one day and start moving things around in your space, asking her what she hears or doesn't hear. See if that helps things. If you can find a way to listen to your music at the volume you like that she finds more tolerable that makes both of you happy.

Posted by: guest at May 4, 2008 9:15 AM in response to Party wall soundproofing

A few comments from above:

#1 if you hear sound through a wall, this does NOT mean fire can come through. The block wall, and other concrete partitions, are resonating in the vocal sound range. This is not due to holes in the block.

#2 Standard cheap fiberglass will work as well as anything. Cotton is very expensive, and cellulose does not work any better. Foam is the worst. Look at the dozens of tests done by the NRC in Canada. The finest acoustics lab in North America. Clearly demonstrated that cheap fiberglass was as good as it gets.

#3 Building a small wall in front of the block wall is an excellent idea. Use 2x4 wood or steel studs, or even 2x3 steel. Just don't have the studs contact the existing wall. This is "decoupling" the new wall from the old wall.

#4 Installing these things, including the green glue that was mentioned, can be done by a drywaller or handyman.

Posted by: guest at May 7, 2008 10:32 AM in response to Party wall soundproofing

When you are dealing with sonics or sound you have to take into consideration the frequency range you are dealing with( high hertz, low hertz)and the presence of sound pressure levels(movement of air)as sound. A large truck passing a house creates noise and a sound pressure that the house picks up due to it's size as a receiver. This sound that you probably would not be bothered by is amplified by the wall of the house. In the case of room to room sound proofing it must be a system not just a sound attenuator. Sheetrock or plaster fastened to a wood stud common to both rooms will transmit sound no matter how much foam or fiberglass you put in the wall, the studs must offset or the use of a foam board attenuator on one side will be needed. The most ideal method of floor to floor or room to room is 1" of closed cell SPF and 2.5" of open cell SPF with a 1/2" foam board under the sheet rock. You can achieve a 65 or better with this system if a common duct system is not in use.Licensed P.E.@BPL.

Posted by: guest at July 10, 2008 4:59 PM in response to Party wall soundproofing

Closed cell foam on studs is a pretty bad idea. First, as a decoupling material it is far too stiff. Along the lines of soundboard, which isn't saying a lot. Offsetting studs or using resilient clips or channel on the studs is a great idea.

Closed cell foam doesn't decouple well, and by virtue of the closed cell nature, is a poor material choice for sound absorption. This has been well documented by the NRC in Canada.

Posted by: JamesW at July 24, 2008 12:25 PM in response to Party wall soundproofing