Replies

1. 
   fingersandtoes | Oct 19, 2009 06:15pm | #1

   Since you are leaving the bedroom side I would start by sealing all openings and joints in the existing drywall. Fill the stud cavities with rock wool batts, apply res bar and RSIC sound isolation clips. Drywall with 2 layers of regular 1/2" and caulk all joints and perimeter before mudding.

   For reassurance this will work, try Googling wall assemblies. This one should test out at around 60 STC.

2. 
   popawheelie | Oct 19, 2009 06:16pm | #2

   It depends on how sound proof you want it.

   Just stuffing the bays with fiberglass will help.

   Doubling up the drywall will help as well. You can fur out/isolate the drywall as well.

   Those are a coulpe of methods that are minimum and not that exspensive.

   "There are three kinds of men: The one that learns by reading, the few who learn by observation and the rest of them have to pee on the electric fence for themselves."
   Will Rogers
3. 
   PeterJ | Oct 19, 2009 10:01pm | #3

   Two things to consider; there's airborne sound, and structure borne. Without getting to personal, what sort if noise you trying to mitigate?

   BTW, I've got a few tubes of Green Glue left over from job I'll make you a deal on. It's not a magic bullet, but will contribute to overall STC rating if other methods are employed as well.

   I've done gobs of research, and put some into practice. I'm convinced that sound mitigation and containment can be a hot bed of conflicting theory and hyperbole. Doing one wall will not soundproof any one room. There's just too many contributing and interrelated factors.

   I can put you onto lots of reading if you wanna make your head swim, or you can take the suggestions already given and probably get 60% of what's possible without going to great measures. 

    

   Everything will be okay in the end.  If it's not okay, it's not the end. 

1. 
   paulinwoodinville | Oct 20, 2009 01:41am | #5

   Thanks Peter......No, I don't need more reading. I've spent hours online investigating, that's why I've come here to ask what's worked for others. Knowing that there will still be noise coming in from the front door/entry/door into master... side of the Master, that's why I hesitate to invest the money for the living room wall. I was hoping to mitigate conversation noise from the living room.
   I'm thinking I will leave the drywall on existing wall, hang RC channel with a piece of torch down roofing behind channel where I screw into existing studs. Then put 2 layers of 1/2 or 5/8 board onto the channel. Am I kidding myself...thinking more sheet rock (mass) will make that much of a difference? Paul

1. 
   PeterJ | Oct 20, 2009 02:07am | #6

   That's the thing, how does one quantify "that much of a difference". You're already finishing rock so I'd go for it. Seal perimeter of first layer (cheap caulk). Fingers had good advice for not much $$.  From the back of  bedroom wall moving towards living, I'd suggest seal, insulate, isolate  2 rock layers on channels. Use construction adhesive and minimize fasteners I think that'll get you where you want to go without lots of money but a bit more time. 

   Everything will be okay in the end.  If it's not okay, it's not the end. 

2. 
   fingersandtoes | Oct 20, 2009 03:15am | #8

   You are going in the right direction. With what you are describing conversation sound will be distinctly reduced. I would consider using the sound isolation clips as well as the channel, they make a lot of difference.

1. 
   klhoush | Oct 20, 2009 05:41am | #10

   Iso Max claims an STC of 57. And that's with R-19 packed into the space.

   Deitrich deluxe gets 57 with one layer of drywall in independant testing:

   http://www.pac-intl.com/pdf/IN09_737_Submitted.pdf

   Installation is important. The studs should line up with one of the holes in the side of the RC. Also the horizontal RC should hang with the nailing flange downwards. Use 7/8" screws to prevent contact with studs. Pretty simple.

   OB

   Edited 10/19/2009 10:48 pm ET by klhoush

   Edited 10/19/2009 11:05 pm ET by klhoush

1. 
   fingersandtoes | Oct 20, 2009 06:01am | #11

   That is pretty good. RSIC-1 clips get 56 with one layer. Two gives you 60. I am surprised to see numbers that high for channel alone. It must be a big improvement over the common rez bar.

2. 
   klhoush | Oct 20, 2009 06:11am | #13

   I wonder how the iso clips will perform in 10 or 20 years when that rubber has dried out or been crushed. Just wondering. Still if the plans show 'em, on they go!

   OB

3. 
   fingersandtoes | Oct 20, 2009 07:25am | #14

   That PFD is interesting. I had never seen numbers for the reduction caused by sandwiching the bar between layers. I knew it was bad - but 20 points! That is funny, because it is often the first thing builders suggest so they don't have to remove the existing drywall.

   You have definitely converted me. If you can get an STC of 63 with their bar it is the way to go.

3. 
   betterbuiltnyc | Oct 20, 2009 03:46am | #9

   I've used Green Glue on several projects, and been happy with the results. We also go nuts with foam and soundproofing caulks, and pay attention to mechanical penetrations, making sure they get sealed tight. We've also worked with RC and insulation--I like GG for ease of install and it doesn't take much extra space.

4. 
   Zano | Oct 20, 2009 01:17am | #4

   Use sound attentuation blankets in between studs, RC-1 channel on side of the wall and heavy drywall glue on the other, use a double layer of 1/2" or 3/8"..try to use minimun nails and screws. Glue asts as a rubbery cushion to prevent the vibrations.

   The drywall is like an audio speaker..the framing members thru vibrations transmit the sound to the drywall which amplifies it.

   There is also a sound proof board..very expensive..as an alternative...just cannot recall the name..google "sound proof drywall".

5. 
   klhoush | Oct 20, 2009 03:10am | #7

   I've had good luck with R-13, R-Channel, and then drywall as usual. It's a noticable improvement. Use the "deluxe" channel. More sound will come in around the door than through the wall. I've never had a complaint after installing with this method.

    http://www.dietrichindustries.com/products/pdf/52_53_DMF07.PDF

   Just screw the R-C directly over the existing wallboard and screw on two layers of 5/8 to get 2 1/4", or whatever works. Don't burn out on it, get it installed and move on. It will be so much better! 

   It's just a house. If people in the other room are noisy, tell them to pipe down! 

   OB

6. 
   carrier63 | Oct 20, 2009 06:10am | #12

   More mass will certainly help. There is a significant improvement by simply adding a layer of rock even without the RC system. From what I've read on the AVS Forum site (audio video stuff) the RC system can help, but it must be installed perfectly or you negate the isolation effect.

   I used Wall Damp peel and stick material from ASC http://www.asc-soundproof.com/ between two layers of 1/2 rock on my basement ceiling in my HT. It worked great and is much easier to install than the RC product. I tried a sound test after the first layer of rock went up and then after the second. There was a huge improvement.

    

1. 
   TedWhite | Dec 29, 2009 10:10am | #15

   This is an older thread, and I found it during a search. Since I found it, others will also, and I'm compelled to correct one common (serious) error in a few of the posts.

   You never, ever, ever want to install a channel or clip+channel array over existing drywall. This creates a Triple Leaf and any improvements will be so minimal as to make the whole process meaningless. You really have only two choices:

   -Remove the existing drywall, and THEN add the clips + channel to decouple the new drywall from the studs.

   OR

   - Keep the original drywall in place and simply add more drywall for mass. Consider damping the drywall.