Can someone tell me if it really make sense to stagger shared wall in a townhouse. And also does it make any difference in sound absorption if I staggered the outside wall. My theater room has four sides with the studs already up. Two of the wall are shared with the neighbors, one of the wall is an outside wall and the fourth wall is facing a hallway. If it were you, which of these wall would you stagger?
Staggering wall studs
- Thread starter gasbie
- Start date
Desert_AIP
Senior Member
Staggered stud walls, say 2x6 sill with staggered 2x4 studs on 16" or 24" centers are used in theater rooms specifically for sound attenuation.
The two wall surfaces are physically decoupled so they don't transmit sound. The space in between is filled with insualtion, even in interior walls, to further dampen the transmitted sound.
So yes it would make sense to stagger the studs on a common wall.
Many town houses I've seen are built with two completely seperate (but joined) walls as the common wall.
Like a double wall with sheetrock in the middle for fire protection.
The two wall surfaces are physically decoupled so they don't transmit sound. The space in between is filled with insualtion, even in interior walls, to further dampen the transmitted sound.
So yes it would make sense to stagger the studs on a common wall.
Many town houses I've seen are built with two completely seperate (but joined) walls as the common wall.
Like a double wall with sheetrock in the middle for fire protection.
Deane Johnson
Active Member
Staggered wall studs are for the purpose of eliminating a path for the sound. A very simple illustration is that the wallboard on each side acts as a drum head. With a single stud, with wallboard fastened to each side, the sound hits one side, starts it to vibrating, the vibration follows the stud to the other side, causing the wallboard on the other side to vibrate, reproducing the original sound in the next room.
So, to if it were mine, and I had the option to do so, I would stagger the walls shared with the neighbors. Otherwise, you're not going to be able to operate the theater sound as you might want to. Even with staggered walls, you will probably have some issues with sound transfer.
Remember, there is a difference between dealing with sound that is reflected back into the room that affects your listening experience, and the sound that escapes the room and annoys someone else.
So, to if it were mine, and I had the option to do so, I would stagger the walls shared with the neighbors. Otherwise, you're not going to be able to operate the theater sound as you might want to. Even with staggered walls, you will probably have some issues with sound transfer.
Remember, there is a difference between dealing with sound that is reflected back into the room that affects your listening experience, and the sound that escapes the room and annoys someone else.
apostolakisl
Senior Member
If you have the drywall down, it definitely makes sense to stagger the studs. It helps a lot with sound attenuation. Rip down a 2x4 to about 1 x 2 and add it to the current sill and top plate making them just a bit wider. 1 inch is more than you need but if you try getting narrower the piece of wood will probably split when you nail it.
I would go 24 on center with your new wall. Plan ahead as to exactly where your 4x8 sheets of drywall will go so that you hit the seams on a stud. They don't have to be exactly 24 on center provided your seems are all on studs. This will help you work around the old studs if they are 16 on center or if there are fixtures in the wall.
Pack the wall with insulation. Cotton batts if you have the cash, otherwise I would go with rockwool.
I would go 24 on center with your new wall. Plan ahead as to exactly where your 4x8 sheets of drywall will go so that you hit the seams on a stud. They don't have to be exactly 24 on center provided your seems are all on studs. This will help you work around the old studs if they are 16 on center or if there are fixtures in the wall.
Pack the wall with insulation. Cotton batts if you have the cash, otherwise I would go with rockwool.
Neurorad
Senior Member
I'd spend the extra, and do staggered studs. Though sound transmission may still be a significant problem. Do what you can afford to do.
As Lou and others alluded to above, there is more that can be done, if you have the cash. Double stud/double wall/room within a room, whisper clips, double/triple drywall, Green Glue, QuietRock, and mass loaded vinyl.
If you would consider installing more than staggered studs, check out soudproofingcompany.com. Lots of reading material on their website.
As Lou and others alluded to above, there is more that can be done, if you have the cash. Double stud/double wall/room within a room, whisper clips, double/triple drywall, Green Glue, QuietRock, and mass loaded vinyl.
If you would consider installing more than staggered studs, check out soudproofingcompany.com. Lots of reading material on their website.
apostolakisl
Senior Member
Just replace the air in the wall with insulation, the same as for heat. Don't pack it super tight or it will serve as a sound coupler. Just loose and fluffy filling all the space up.
Thanks guys for your contribution. Here is my update.
My living room on the middle floor is sharing a wall with my neighbor. The shared wall is not insulated. I made a hole into the wall and realized that the studs used for constructing the wall is not touching the firewall that was used to separate each unit. I felt this was like a staggered wall. Therefore if the studs vibrates, it won't transfer sound easily to the other side of the wall. Correct me if am wrong. Anyways, I decided to carry out my sound check today. I called my neighbor up to let her know that I will be doing my sound check and she should let me know when the sound becomes unbearable. I moved my speakers closer to the wall. She asked me to crank the volume up which I did, then it got to a point where she told me to stop. At this point, she said that she could only hear it a little bit which she doesnt mind. Funny enough, her stopping point was too loud for me. She was also surprised that it took that much volume to vibrate her unit. She responded," you really had a well constructed wall in your unit". I took it has a compliment.
But anyways, I still planning on putting my green wall to that share wall, then I can rest assure that soundproofing will even get better. I have posted some pictures of my basement in this thread. I have some question that I will need someone to help me out. My ceiling is not that high, so, should I use s mixture of 1/2" drywall + gg + 5/8" drywall? That way, I don't really compromise the height of the room. Also, the studs facing my neighbors on both side is not touching the wall, does any know if I still need to stagger these four walls even though they not touching the other wall?
How can I work around the door area because I know that using 2 5/8" drywall on this area will consume the door? how can I make things work?
On the way, am using 2 5/8" drywall with green glue, on the ceiling (due to the height restriction) am thinking of using 1/2 + gg + 5/8 or 1/2 + gg+ 1/12:
Also, I will using roxul insulation. As you can see, I have alot of can lights in there. I was just thinking if I can just build a long box for each roll of can instead of building it individually. Please refer to my diagram.
My living room on the middle floor is sharing a wall with my neighbor. The shared wall is not insulated. I made a hole into the wall and realized that the studs used for constructing the wall is not touching the firewall that was used to separate each unit. I felt this was like a staggered wall. Therefore if the studs vibrates, it won't transfer sound easily to the other side of the wall. Correct me if am wrong. Anyways, I decided to carry out my sound check today. I called my neighbor up to let her know that I will be doing my sound check and she should let me know when the sound becomes unbearable. I moved my speakers closer to the wall. She asked me to crank the volume up which I did, then it got to a point where she told me to stop. At this point, she said that she could only hear it a little bit which she doesnt mind. Funny enough, her stopping point was too loud for me. She was also surprised that it took that much volume to vibrate her unit. She responded," you really had a well constructed wall in your unit". I took it has a compliment.
But anyways, I still planning on putting my green wall to that share wall, then I can rest assure that soundproofing will even get better. I have posted some pictures of my basement in this thread. I have some question that I will need someone to help me out. My ceiling is not that high, so, should I use s mixture of 1/2" drywall + gg + 5/8" drywall? That way, I don't really compromise the height of the room. Also, the studs facing my neighbors on both side is not touching the wall, does any know if I still need to stagger these four walls even though they not touching the other wall?
How can I work around the door area because I know that using 2 5/8" drywall on this area will consume the door? how can I make things work?
On the way, am using 2 5/8" drywall with green glue, on the ceiling (due to the height restriction) am thinking of using 1/2 + gg + 5/8 or 1/2 + gg+ 1/12:
Also, I will using roxul insulation. As you can see, I have alot of can lights in there. I was just thinking if I can just build a long box for each roll of can instead of building it individually. Please refer to my diagram.
Attachments
Deane Johnson
Active Member
Gasbie, in any additional testing you do, be aware that the extreme low frequencies like those from a sub will travel through things more than the higher frequencies. For that reason, it's good to test with the booming of a sub if that's what you'll be using.
apostolakisl
Senior Member
I wanted to clear some things up.
1) Your condo is multi-floor and you ocupy all of them.
2) The room you are playing the music that needs insulating is on the first floor.
3) You have a basement under that room.
4) Your basement has a cinder block or poured cement wall between you and your neighbor.
5) There is a second floor above the room you are going to be sound proofing.
That is great news that you already have separate walls for you and your neighbor. I would still fill the wall with insulation since the cost and labor aren't very high.
I am a little confused on the basement. I will hold off on comment until you confirm the above points.
1) Your condo is multi-floor and you ocupy all of them.
2) The room you are playing the music that needs insulating is on the first floor.
3) You have a basement under that room.
4) Your basement has a cinder block or poured cement wall between you and your neighbor.
5) There is a second floor above the room you are going to be sound proofing.
That is great news that you already have separate walls for you and your neighbor. I would still fill the wall with insulation since the cost and labor aren't very high.
I am a little confused on the basement. I will hold off on comment until you confirm the above points.
apostolakisl
Senior Member
Great, so you are looking at sound proofing your basement ceiling. Are you trying to keep the sound from the room above out or are you trying to keep basement sounds in? Or is this part of the plan to keep sound from getting to your neighbors?
Lou Apo, Yes am trying to keep the sound from the room above out and am also trying to keep sound from escaping through the basement wall. Like I said earlier, I have a separate wall (in other words, my studs are not touching teh share concrete in any way, so I have ruled out staggering my wall. I have decided to install roxul AFB insulation in the basement. My only concern is the height of my ceiling. Right now, my ceiling is about 8' tall. so if I install two 5/8" drywall wall, that will compromise the height of my basement. how would you treat this situation? thanks
apostolakisl
Senior Member
Treating the ceiling of your basement is of course a fine idea to keep sound from the room above out, but it isn't likely to be of any benefit keeping sound out of the neighbors house. If you have a poured cement wall between you and your neighbor that is going to stop most any sound, even a cinder block wall would do the trick.
You do need to concern yourself with the area above the ceiling and below the floor. . . the joist space area. This is important even if you also sound insulate the basement ceiling. If the joists run perpendicular to the common wall, cut pieces of drywall to fit between the joists (blocking) and install them against the neighbor. You can put two layers with GG between them and then caulk around the edge. If the joists run parralel, it will be easier, you can just cut one big long one.
From the sound of things (no pun intended), I think the builder of your place probably has wood blocking at the joist space level between you and your neighbor. I would bet that fire code requires it. So, you may not need to get that crazy with adding more blocking, but this is a bigger risk of sound leak than the cement wall below it.
As far as keeping the sound out of the basement, your can lights are going to really hurt you. Your question above I think has a typo, and I think I am understanding you to be asking if you can build a single box that includes multiple cans. I don't see any reason why you can't. If your box is soundproofed to the same level that the ceiling is, then it should all be the same. You might have trouble installing such a box with plumbing and wires in the way however. Don't forget about the fact that the cans you have in your basement are going to need some air space around them since I doubt the builder would have put the insulatable cans in a basement ceiling.
You do need to concern yourself with the area above the ceiling and below the floor. . . the joist space area. This is important even if you also sound insulate the basement ceiling. If the joists run perpendicular to the common wall, cut pieces of drywall to fit between the joists (blocking) and install them against the neighbor. You can put two layers with GG between them and then caulk around the edge. If the joists run parralel, it will be easier, you can just cut one big long one.
From the sound of things (no pun intended), I think the builder of your place probably has wood blocking at the joist space level between you and your neighbor. I would bet that fire code requires it. So, you may not need to get that crazy with adding more blocking, but this is a bigger risk of sound leak than the cement wall below it.
As far as keeping the sound out of the basement, your can lights are going to really hurt you. Your question above I think has a typo, and I think I am understanding you to be asking if you can build a single box that includes multiple cans. I don't see any reason why you can't. If your box is soundproofed to the same level that the ceiling is, then it should all be the same. You might have trouble installing such a box with plumbing and wires in the way however. Don't forget about the fact that the cans you have in your basement are going to need some air space around them since I doubt the builder would have put the insulatable cans in a basement ceiling.
