Stud walls around WC/showers

[WWilts]

New build in progress. 

Stud walls preferably to not transmit too much sound, esp from WCs/showers & between adjoining bedrooms. (pic)
 

First floor height to ceiling 2300mm.

 

Qus:

A. Would CLS studs 50x75 suffice? Staggered studs. (actually 38x63)
Would C24 (or C16) timber 2"x4" for studs offer any advantages in terms of 

a) structural strength

b) sound proofing
Some say CLS is less likely to twist, compared to sawn timber.

 

B. Would OSB backing board on noggings suffice wherever stuff is to be fixed to the stud wall later? If yes, what thickness of OSB? (9, 11, 15, 18mm)?

 

 

 

[Temp]

We have a wall between two bathrooms. Its got 100mm studs and both sides clad with 12mm Hardi Backer board (heavier then normal plasterboard). One side is also covered with 15mm limestone tiles. The stud work is filled with sound insulation but the studs bypass this.  Right now you can hear someone talking to themselves in the shower through the wall. 

 

I'm thinking you definitely want staggered studs each supporting just one side with sound insulation woven between.

 

 

 

 

 

[Conor]

I can highly recommend 70mm metal studs. We have 70mm wall with 50mm accoustic insulation, 18mm ply lined on one side and 12.5mm plasterboard on each side. We have this between our two offices and you can't hear a thing through it.

[WWilts]

15 minutes ago, Conor said:

70mm wall with 50mm accoustic insulation, 18mm ply lined on one side and 12.5mm plasterboard on each side.

Is the ply thought to be crucial? 
 

[Conor]

3 minutes ago, WWilts said:

Is the ply thought to be crucial? 
 

No. It was to preempt lots of shelf fitting in the office! We did this in bathrooms etc as well. Can't objectively say if it's quieter than just plasterboard. But compared to my parents house that is timber stud, it's night and day.

[Conor]

Just now, Conor said:

No. It was to preempt lots of shelf fitting in the office! We did this in bathrooms etc as well. Can't objectively say if it's quieter than just plasterboard. But compared to my parents house that is timber stud, it's night and day.

 

Edit: I used 12mm OSB in most other rooms as much, much cheaper but still strong enough to mount sinks, rads, etc.

[nod]

Timber is rubbish for sound transmission 

We have two 70 mil mf studs between two bathrooms Both have a loo on each side 

You cant here either loo flush 

 

makeup 

70 mil mf studs x 2 100 mill cavity 25 mil acoustic insulation 1 sheet x 2 of 15 mil moister soundblock PB

Tiled on either side