DIY Home Improvement Forum banner

Reduce Noise Between Interior Bedroom Walls

1168 Views 11 Replies 9 Participants Last post by  brentvw
Reduce Noise Between Interior Bedroom Walls

I thought this would be a simple project but reading a lot of conflicting information. We have a new build finished home, contractor grade. We can hear conversations between the bedroom walls like there is no privacy, even light snoring would wake you up in the next bedroom. I'm assuming there is only 1/4" drywall on each side and empty stud cavities making for a nice echo.

So what is best way to reduce the sound between the walls? I don't want to use the word "soundproof" as that starts yielding super crazy options.

1) hanging 5/8" quietrock over existing drywall (expensive and thick)
2) Adding 1/4" drywall with a sound dampening green glue (messy)
3) Tearing out existing drywall, putting in rolled insulation (excessive?)
4) Blowing in insulation (leaves huge holes)
5) combination of the above, i.e. - #3 and #1

Tearing out seems messy, adding means redoing trim and doors. I'm leaning to blown in cellulose as the least painful of the options and a good starting point but those huge holes are ridiculous, at least 1/4 the drywall is drilled an patched, would it keep a clean look?

Is there a simple answer to this I'm not thinking about that isn't crazy or overkill? What would you do? (please don't say earplugs)
1 - 12 of 12 Posts
Don't be afraid of doing drywall work. Now that you have a new house, you get to do all sorts of fun projects.

First, air gaps will transmit sound very well. Bottom of door may need a sweep. If you have forced air heating, common ducts or returns can transmit sound (no easy fix for that).

Rockwool Safe N Sound is commonly used for your type of problem. After that, I can only think of the Quietrock --- pretty expensive stuff, actually.

Never heard of using cellulose for sound absorption - maybe it works. Very unlikely your drywall is 1/4" --- in all likelihood its 1/2". Remove a wallplate if you want to see.

  • Like
Reactions: 1
I doubt you have 1/4" drywall, that stuff is kind of special use; walls are normally 1/2" rock.

Is there HVAC connecting the rooms? If so, messing with the wall all day long may result in no effect. Figure out where the sound is being transmitted - if you're sure it's through the wall system, then Safe N Sound would be the way I would proceed.
If you go with blown in I would start with the electric outlets and switches with sound putty. by cutting holes from the other side.

So you would have patches to fix one the other side of outlets in both rooms.

  • Like
Reactions: 2
Hi Brent, just thinking out loud.
Rockboard is a mineral wool product available in 4x8 sheets and faced with foil. I'm pulling this from a search, never used it.

But there would be no issues with needing to cover it with a thermal barrier like most foam boards and you would have a bit of an industrial look with taped seams but could paint it. Could also use strapping.

At receptacles you could just leave a larger opening and use foil tape on the edges.

Point here is no removal of existing walls or adding new drywall.

Like i said, just thinking.

Perhaps your new dungeon would be best in the basement?
I'm looking into "Pour-in-place" /open cell/ foam for my interior walls. They make kits where you can do it yourself for a couple grand - the stuff I was looking at (Handi-Flow) didn't require a huge hole or anything and it goes at the top of the wall and could be easily covered by crown molding.
Blown in insulation is tricky I think. It would have to be fairly dense packed and that's not possible without lots of experience. It is also very dusty and not sure which you can live with: emptying the room or some drywall removal or such work. The holes drilled would have to be patched and the walls repainted. I don't think you can avoid those repairs.

The green caulk is very expensive, although there is lots of good opinions. But no matter how much you want to avoid the mess of the work, there is only one way sound proofing (attenuation, whatever you want to call it) can work, which is to absorb the sound waves and to block it (not sure if these things mean the same or if there's difference). LIttle things probably will not help since those are little touches that adds, but not a factor in itself.

Check the videos as well. One sensible comment was to use fiberglass insulation (or rockwool) in the wall cavities and then use 2 layers of drywall. The video talked about 2 layers of 5/8" sheetrock, but I think I personally would be ok with 2 layers of half inch sheetrock.
See less See more
all, greatly appreciate the replies

based on this discussion going to:

1) tear out the existing 1/2" drywall
2) fill with roxul rockwool safe n' sound insulation
3) put quiet rock putty pads over all the gangs and switches
4) add one sheet 4x8 1/2" quiet rock drywall - keep trim and door jams the same
5) add small bead of acoustical sealant around the boards, floor and ceiling as per mfg instructions

doing this to about 20' of wall on one side, avoids the mess of blown-in and doesn't expand the wall footprint

looking forward to the outcome, only challenges is the 1/2" quiet rock has to be cut with a saw, doesn't score and snap like the 5/8", also have to be careful with mud and tape around acoustical sealant as it never dries but stays sticky to absorb the sound

all in all, looking forward to the project
See less See more
  • Like
Reactions: 2

Project complete. Tore out existing 1/2", installed the roxul safe n' sound insulation, added 1/2" quietrock and put acoustical sealant around all edges with putty pads on outlets.

I'd say sound is reduced by 70% and is where we need it to be. You can no longer hear snoring between the bedrooms, or TV on a low volume, phone conversations also sound distant and muffled vs hearing every word.

Adding another sheet of quietrock to the other side of the wall would probably get this to 90%+, but will see for now.

Thanks all for the advice
brentvw said: Adding another sheet of quietrock to the other side of the wall would probably get this to 90%+, but will see for now.

Thanks all for the advice

Now that you're not working as much, the "friendly marital relations" will be much more fun !!!!:wink2:I personally think the time and cost was worth it.:biggrin2: No more answering "what was all that noise Dad ?? "
1 - 12 of 12 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.