Extension starting soon and I have a question about stud wal

[skipdiver]

4"x2" for me at 400 centres. Worth the extra cost and i'd maybe use soundbloc PB as well, depending on the situation. If i was having an extension built, i'd probably get the builders to throw up a breeze block wall while they are at it.

 

[Obi Wan Kenobi]

What size are the stud walls? I'm not disagreeing with any advice on here but I think 3x2 with 12.5 mm t/e plasterboard and thistle multi skim coat is fine. Definitely 400 centres and don't forget the noggins

Obi Wan

 

[markblue777]

They are not long walls. Typically 1400mm long one is maybe 1500. They are 3m high. I am looking at 75x45mm now and seems a decent size but may go up to the 4x2 CLS I know they are only 89x38 but I think that would be enough.

 

[markblue777]

Can then wedge out the sound proofing in that thickness

 

[markblue777]

The Rockwell sound roofing is that the 600 wide lot? Do you just trim the extra off and put it in another? Or do they do a 400 wide?

 

[RogerS]

I'd go the 4x2 on 400mm centres. Currently doing a lot of studding in the house renovation and the difference between using 3x2 and 4x2 is very marked.

Second the recommendation to use a proper tile-backer board but not Hardiebacker. Very heavy and a bu**er to cut. Knauff make much lighter stuff ..Aquapanel IIRC . Wickes stock it.

 

[Beau]

I did a dividing wall here that we we were pushed for space so used 3x2. It's perfectly good but I would go to 400 centres.

 

[MikeK]

Doug71 and the others are correct about methods to reduce the sound transmission through the walls. I design and build facilities where we must meet strict sound abatement requirements for the rooms, and mass is your friend when building acoustic walls. We start with rock wool insulation that weighs at least six pounds per cubic foot and pack it as tightly as we can between the wall studs. We use two layers of 20mm gypsum wall board on each side of the studs and completely seal the first layer before we put the second layer on. I haven't had a wall fail the sound transmission test yet.

 

[Beau]

Doug71 and the others are correct about methods to reduce the sound transmission through the walls. I design and build facilities where we must meet strict sound abatement requirements for the rooms, and mass is your friend when building acoustic walls. We start with rock wool insulation that weighs at least six pounds per cubic foot and pack it as tightly as we can between the wall studs. We use two layers of 20mm gypsum wall board on each side of the studs and completely seal the first layer before we put the second layer on. I haven't had a wall fail the sound transmission test yet.

Think for soundproofing the insulation you want is RS60 which is a high density Rockwool. The other thing that can help is resilient strips which help decouple the plasterboard from the stud work

 

[MikeK]

Think for soundproofing the insulation you want is RS60 which is a high density Rockwool.

RS60 is 60kg per cubic meter, which is about 3.75 pounds per cubic foot. The stuff we use has a equivalent mass of 96kg per cubic meter, which is almost the same rating as RS100 rock wool. In this case, more mass is better.

In special installations, we will use a separate row of studs for each side of the wall, separated by two inches inside the wall. The entire cavity is firmly packed with the rock wool and all wiring is in surface-mounted channel.