A few quick questions about soundproofing

[fistameeny]

Hi all,
I'm currently in the process of soundproofing a party wall in a bedroom. I have a few small questions to sort before I crack on with it:

1) If I'm putting some Rockwool RWA45 under the floor boards between the ground and first floors, do I need to use chicken wire to hold it up? I'll be putting it in from above, but is the chicken wire used to keep the weight off the plaster board below, or for fire prevention etc?

2) What length of screws should I be using to attach the uprights to the wall? (they are 75mm deep batons). I was thinking of using one layer of acoustic plasterboard (which I believe is 36KG per 2.4m x 1.2m sheet) attached to resilient bars.

3) What type/length of screws should I be using to attach the resilient bars to the uprights, and then what type to attach the acoustic plasterboard to the resilient bars?

Thanks in advance.

 

[PrenticeBoyofDerry]

1) no need, the mesh is used to support the insulation from underneath to keep it in place. Prior to boarding out.

2) don't understand your questions, is it regarding building a stud wall, if so 100mm screws.

3) using 32mm for both is normally good enough.

Things to remember;
Electric power cables, should not be totally surrounded by thermal insulation.
The insulation within the floor/ceiling void will prevent warm air traveling to the rooms above.

 

[fistameeny]

1) no need, the mesh is used to support the insulation from underneath to keep it in place. Prior to boarding out.

2) don't understand your questions, is it regarding building a stud wall, if so 100mm screws.

3) using 32mm for both is normally good enough.

Things to remember;
Electric power cables, should not be totally surrounded by thermal insulation.
The insulation within the floor/ceiling void will prevent warm air traveling to the rooms above.

Thanks for your reply. Regarding 2) - I'm attaching 75mm batons to a brick wall, then attaching 2 layers of acoustic plasterboard to resilient bars, attached to the batons. I want to be sure that the plasterboard etc isn't going to detach from the brick wall due to the weight.

Will 100mm screws by OK for this?

 

[PrenticeBoyofDerry]

Sound a bit chunky for a battened wall, I would be using something nearer 38mm timbers, if screwing back to masonry.
But if you are using 75mm, you would be best fitting a sole plate and header plate, so to get a good solid, sound structure and build as if building a stud wall, without relying on screwing in to masonry.
If you fell you need to, make sure you get a good countersink in to the timber. So you are getting at least 40mm of the screw in to the wall you are fixing to.

 

[fistameeny]

Hi,
I'm using 75mm to get a good thickness of acoustic insulation in. I've already countersunk the batons, so will pick up some 100mm screws and get cracking. Thanks for your help.

 

[ajrobb]

Your right that extra thickness will give some extra isolation. However, acoustic partitions often use flexible mounts rather than stiff mounts. With stiff mounts you risk getting energy into the plasterboard through the flanks (floor, ceiling and end walls).

If you have 83 mm to play with, you could use GypWall Quiet IWL system, which is an approved Robust Detail for separating dwellings.