Soundproofing Question (1 Viewer)

[Greg Foan]

Hello,
I've decided to double drywall the walls and ceiling of my recroom/HT with a 1 inch airspace between layers as advised by the many geniuses on this site. My question is this: The South wall is a HCB wall that has been framed, insulated and drywalled already.It seperates the HT from the storage room. Is there any advantage to adding the 2nd layer to this wall? Also, the West wall is the a HCB perimeter wall that has been framed / insulated / drywalled as well. Does it make sense to add the 2nd layer to this wall? The other 2 walls have rooms adjacent to them and the ceiling is right under the livingroom so doing them them only makes sense. Thanks in advance for your help.
Greg

 

[johnbr]

Greg You should look at this http://www.tubetrap.com Look at Iso walldamp contruction system it has a lot of good info.

 

[Greg Foan]

John,
Looks like interesting stuff.......but out of my league by the look of their estimator software. I'd be looking at nearly $11,000 based on a 16.5 X 17.33 room.

 

[Greg Foan]

Anyone else care to offer an opinion re: my original question? I'd appreciate any input offered.
Thanks,

 

[RAF]

Greg,
According to the people at tubetrap.com (who just e-mailed me) the calculated amount would be closer to $2,200 and NOT the higher figure you quoted.
Please e-mail me (not private message, please!) if you want the e-mail address of the individual who told me this.

 

[Scott-C]

I've decided to double drywall the walls and ceiling of my recroom/HT with a 1 inch airspace between layers as advised by the many geniuses on this site

Anyone have any good instructional links on how to do this?

Thanks!

 

[Chad Anson]

The term "double drywall" is a bit misleading. For sound isolation, you essentially want to build a room within the existing room where the structure of the "inner" room is sonically decoupled from the rest of the structure. Ideally, you would frame the inner walls with a 1" gap from the "outer" wall, and would do the same thing with the ceiling (sometimes referred to as a "floating ceiling"). Decoupling the wall from the floor is a bit trickier, but they sell u-shaped rubberized channels that do the job. Some folks will lay down some acoustical caulk before attaching the baseplate, others just don't worry about it. See http://www.avsforum.com/avs-vb/showt...oating+drywall for a more detailed description.
Now back to Greg's question. . . there may be two reasons for doing the south and west walls. (1) if all four walls aren't treated sound could potentially leak upwards around the floating ceiling (through the storage room or in the west wall); and (2) I've always read that the inner walls/ceiling should be constructed with two layers of drywall attached to the studs (e.g., a 1/2" sheet and a 5/8" sheet, ) using screws and glue and using acoustical caulk on all seams/electrical boxes, etc. It would seem to me that if only two of your four walls were created this way, the room may sound a bit off... particularly since the side walls would likely reflect sound differently.