Soundproof a wall, what is needed?

[Klicka]

We have moved into a semi-detached house and we can hear the neighbor snoring behind the bedroom wall.

What is needed to dampen the snoring? It's quite low-frequency noise.

Is it enough to make the wall thicker with boards (OSB and plasterboard)?

Will it be better if I build a new inner wall a bit in front of the other wall? What materials do I need?

 

[Jan-Å]

I have read that gypsum boards are good for soundproofing; I believe it is more effective to apply double gypsum on the existing wall than to build another wall with insulation.

 

[anna_jimmy]

Here is a lot of information on how to best solve your problem. Personally, I believe in building a new wall frame in front of the existing one with a separate framework that stands 50 mm in front of the existing wall, creating an air gap in between. Double plasterboard on both sides. But check the link for good answers, http://www.gyproc.se/konstruktioner/innerv%c3%a4ggar/innerv%c3%a4gg+med+h%c3%b6g+ljudreduktion/e-handbok+gyproc+xr+450

 

[Caspár]

When we were renovating, our carpenter told us that each drywall panel, 12mm, removes about 7Db of sound.
We placed that on the existing wall towards the neighbors, we also put plywood first to be able to screw into.

 

[Jan-Å]

Here is lots of info on how to best build away your problem, personally I believe in building a new wall in front of the existing one with a separate frame that stands 50 mm in front of the existing wall so you get an air gap in between. Double gypsum on both sides. But check the link and you should get good answers, [link]

Do you know if such a solution works? I'm not an expert at this, but won't the air gap become a resonance box instead? Air is not a good sound insulator, nor is regular insulation according to our carpenter at work, who recommends more gypsum. On some walls we have glued a special type of sound-deadening panels as well, I'm not sure if that's more effective maybe?

 

[Klicka]

Maybe first try putting up more drywall.

I read somewhere that for low-frequency sounds, air insulates better because structure-borne sound doesn't pass through air as easily. But for high-frequency sounds, thick materials dampen better.

I'll have to think about it.

 

[slacker]

Uncertain, so go with Isover Piano acoustic board - Used this for two similar jobs specifically for interior walls with sound issues. So frame up with 45 stud and install the insulation, add some drywall or whatever you prefer - Perfect!

http://www.beijerbygg.se/templates/BB_ProduktListingFlera.aspx?id=10255

 

[hakaner]

It depends a bit on how it spreads, airborne sound or impact sound. Airborne sound sneaks past gaps, etc.
-So if you attach studs to the existing wall or build a new one, then seal with soft caulk between the wall and floor/sidewall/ceiling.
-What does the ventilation look like? It should ideally be separate, but if, for example, you share an exhaust duct, sound can be heard between rooms through ventilation channels...

 

[Klicka]

Maybe a dumb question. But how is such a Piano soundboard attached between the studs? I won't have any boards on the back supporting the soundboards. So if I assemble the wall 5 cm in front of the existing wall.

 

[raveper]

If you are going to build another wall, there should be a small "air gap" in between. Then, as hakaner writes, it's important that it is sealed properly with sealant all around. Probably insulation and two layers of drywall are enough since you already have a wall. Place string between the studs so that the insulation doesn't fall out the back.

 

[Klicka]

Should you seal around the steel/wood studs against the floor, wall, and ceiling on both sides before attaching the drywall? It might give better results than just sealing on the front side.

 

[vojma]

...in front of the existing one with a separate frame that stands 50 mm in front of the existing wall so you get an air gap in between. Double plasterboard on both sides.

It will likely be difficult to put double plasterboard (or single for that matter) on both sides if you're only going to have a 50 mm gap between the walls.