Soundproofing a Party Wall Using Green Glue

[dmcpherson2007]

I am interested in soundproofing a party wall in my home so I can play my surround system without disturbing the neighbours. Because of the lack of space I am not able to make a stud partition. I know that this is the best option but this is not possible.
What I am thinking of doing is gluing partition to my existing wall (which is also partition) and then overlapping with another layer of partition with green glue in between. I will then seal the edges with acoustic sealer.
Can anyone tell me what sort of soundproofing this will offer. Also, how would I attach the first layer of partition to the existing wall?
Many thanks

[Jon Boy]

Hi DMC, got any pics of the room and the walls, your reply seems a little contradictive.....

Originally Posted by dmcpherson2007

What I am thinking of doing is gluing partition to my existing wall (which is also partition) and then overlapping with another layer of partition with green glue in between

Originally Posted by dmcpherson2007

Because of the lack of space I am not able to make a stud partition

If you could pop a couple of pics up i'm sure i can find a sensible answer for you, i've been a partitioner for the last 9 years

jon

[dmcpherson2007]

Thanks for you reply Jon.
Just read it back to myself and realise what you mean when you say that it is contradictory .

Sorry but I can't take a pic because the camera is playing up and won't allow me to download any pics. Hopefully I'll try to explain a little bit better.

I know that Green Glue has to be sandwiched between two bits of plasterboard. The first layer of plasterboard must be attached to the wall first. Then the second, Greeen glued layer should be attached to the first layer.

The party wall is made of brick. Plasterboard has been glued directly to the brick. As a result when you tap the wall it sounds hollow.

What I wanted to know is how do I attach the first layer plasterborard to the existing wall?
Many Thanks

[Jon Boy]

Right that makes a whole lot more sense to me now hehe

I'm presuming the existing plasterboard is stuck to the wall in a dot and dabbed fashion which makes it a little trickier as you'll have a small cavity behind there so...


Hmmm this one has got me thinking, it's a real shame you cant throw up a 50mm deep metal stud partition against the front of the wall, you'd only lose 75mm off the width of your room!

Stud partition route...

If this is an option you'd fix a metal track section along the floor against the existing wall. Then do the same at the top of the wall into the ceiling. Next cut the studs (all this metal can be cut with tin snips) to the height of the room.
Set one stud at either end of the wall (you just stand them in sideways and twist them into the floor and ceiling channel.
Next from one end of the wall set out the rest of the studs at 600mm centres (the boards are 1200mm wide)
Fix the studs back through the existing wall into the brick using rawl plugs and long screws (maybe 2 1/2" 8's say about 4 per stud.
Then you can board from one end using a full width board and a cut down for width board at the other end.
Then you can apply your green glue.
Finally apply the second layer of board (you may want to go for soundbloc board on the second layer or even both layers) but this time cut a board in half for width so you start with a 600mm wide board thus staggering the joints for extra strength!

Before you board you may want to put some rockwool slab insualtion between the studs, it comes 600mm wide
Also dont forget to get taper edged boards so it can be jointed afterwards unless you're getting it skimmed

Ok so if that's not an option you're still going to have to throw up a frame work that doesnt have to be as deep , maybe out of timber, some 3" x 1" and set it out the same way as i described the stud partition!


Hmmm hope this helps mate, if there's anything else you need to know just ask of if i've totally got the wrong end of the stick let me know and i'll come up with something else!

Cheers

Jon

[Da_Rude_Baboon]

Jon have you any experience of Fermacell boards? These would appear to be a better solution then plasterboard for sound proofing.

[dmcpherson2007]

Thanks again for your reply Jon.

I think that the timber solution would probably be easier for me as i can get the wood from my local Wickes.

Just a couple of questions. Do I need to isolate the studs in any way or do I just screw them into the existing wall? I've heard that an air gap is required to get improved soundproofing. Also, is it necessary to attach the studs to the top and bottom channels as they will be screwed to the wall?

Just one other thing. Someone mentioned that soundproofing may subject to the 'Party Wall Act'. Is the true?

Thanks

[Jon Boy]

No you wont need to isolate the studs.

I would get some cavity fixings to hold the timber studs to the existing wall.

Drill say 4 holes in each of the upright timber studs (one top , one bottom, two inbetween) not too big say with a 1/8 drill bit.
Next postition the timber stud where it needs to go all leveled up. Then with your drill, drill though each of the holes in the stud just enough for the drill bit to exit the rear of the stud and make a mark on the existing plasterboard wall. Repeat this process for each stud.

When you've done that get your cavity fixing and as you can see on the head of it (ignore the screw for a minute) it has a star shaped slot which is for your screwdriver or cordless drill if you have one.
Find the marks you've just made on the existing wall and screw the cavity fixing into the plasterboard, it's corkscrewed as you can see so will drive straight in.

**When purchasing the cavity fixings they dont need to be too long because you dont want to be hitting your breezeblecks behind i'd say go for some 20mm cavity fixings)

Once you have all your cavity fixings in you can fix each stud to the wall one by one. Just stand it back in where you had it before and use the screw provided to fix it. The screw will go through your previously drilled hole in the timber stud and enter the cavity fixing and will do up nice and tight

**If when your fixing the cavity fixing into the existing wall you hit a pit of the board adhsive holding the exisintg plasterboard to the wall dont panic , just drill a new hole in the stud a bit higher or lower than the one you just did.

Cavity fixings dont cost a lot and can be bought at any d.i.y shop.

I cant pass comment on the "air gap" for imporved sound proofing i'm afraid, i cant say if this is true or not.

It's not necessary to fix the uprights to the top and bottom timbers just cut them in between (to be honest if you're going the timber route you dont really need them but it wont hurt to put them in)


"Someone mentioned that soundproofing may subject to the 'Party Wall Act'. Is the true?"

lolol i dont know about that one but it sounds very much like someones having a joke with you lolol

hope this helps

Jon

[dmcpherson2007]

I have some of those cavity wall fixings but I think they are 35mm or so. I have seen the smaller ones in Wickes too.
I know it may sound a silly question but if I use 3" x 1" timber will I put the studs on with the 3" on the wall or the 1"? Ie Which side should be flush with the wall? If the 1" is flush with the wall (making the stud protrude from the wall by 3") will the cavity fixing screw be long enough or would it be ok to countersink.

Also, how will I attach the plasterboard to the studs. Should I use adhesive or screws or even a combination of both?

Funny though. I had never heard of the Party Wall Act before Thought I would ask anyway. Got me a bit worried lol

Thanks for your patience Jon

[Jon Boy]

Originally Posted by dmcpherson2007

I have some of those cavity wall fixings but I think they are 35mm or so. I have seen the smaller ones in Wickes too.
I know it may sound a silly question but if I use 3" x 1" timber will I put the studs on with the 3" on the wall or the 1"? Ie Which side should be flush with the wall? If the 1" is flush with the wall (making the stud protrude from the wall by 3") will the cavity fixing screw be long enough or would it be ok to countersink.

Also, how will I attach the plasterboard to the studs. Should I use adhesive or screws or even a combination of both?

Funny though. I had never heard of the Party Wall Act before Thought I would ask anyway. Got me a bit worried lol

Thanks for your patience Jon

Not a problem mate!

You put the 3" side against the wall so the cavity is only an inch deep! Fix the plasterboards to it with 25mm drywall screws for the first layer (you only need to put say 4 perside) remember the first layer only needs to be tacked on but it doesn't matter if you put lots in!
On the second layer you will need longer screws, 32mm screws dont always bite through so probably safer to git 38mm drywall screws. fix these approg 300mm apart up the sides and up the centre of the board.

Your 35mm cavity fixings will probably be alright, you're covering the existing wall so why not pop in there and try one, if it goes into the existing wall and finished flush you'll know theyre alright!

you wont need any adhesive on any of the wall , espesh as you're using the green glue!

Any other questions feel free to ask

jon

[dmcpherson2007]

As I am now using the timber solution I will only have a one inch cavity. I won't be able to use the 600mm Rockwool. Can you suggest anything else I could use.

Thanks again.

[Jon Boy]

Originally Posted by dmcpherson2007

As I am now using the timber solution I will only have a one inch cavity. I won't be able to use the 600mm Rockwool. Can you suggest anything else I could use.

Thanks again.

I'm sure the off the roll insualtion will squash down fine, it comes in rolls 1200mm wide usually with a perferation in the middle you you can cut it in half and have 2 x rolls 600mm wide.
TBH i wouldn't worry too much, if you want to you could always do two layers of soundbloc instead of one and one normal borad.

Jon

[MarkP80]

dmc, in my opinion, if your new wall is tied back to your existing wall, then the sound will simply be conducted through the connection - particularly the low frequencies, which disturbs the neighbours! Your new wall should be isolated from the existing wall in order to be effective.

You may wish to consider fastening the perimeter of the frame to the ceiling, floor and two side walls, then install the supporting framework between this. The gap doesn't need to be large, but you should fill it with rockwool or similar. Part E of the Building Regs gives lots of guidance on modifying a wall to limit the transmission of sound. I'm pretty sure the old party wall regs no longer apply and are replaced by this. Note however, these regs would only apply if the room was subject to a change of use. An example of this would be say you were doing a loft conversion in a semi. Part E regs apply to the loft wall going into next door's attic, so that would need to be soundproofed to Part E to the building inspector's satisfaction. They don't apply to you here.

You can download Part E here -

http://www.planningportal.gov.uk/eng...000000263.html

Have a look at section 4 for work on existing buildings, especially section 4.22 for wall treatments. Section 4.25 Points To Watch says specifically "Do ensure that the independant panel and its supporting frame are not in contact with the existing wall".

I wouldn't like to think you went to a lot of effort for little return.

Cheers,
MarkP

[dmcpherson2007]

Thanks for your post mark.

One of the reasons I chose to use Green Glue was because it apparently didn't use conventional methods to soundproof a wall. Ie using mass and an air gap.

Because I have an (L) shape front-room (both lengths being almost equal and fairly narrow) I didn't have many options. There was no way that I could lose any more than about 2".

After a bit of research and hairpulling (there were many ways to soundproof) I needed to find out the most practical way that I could do it. Lucky enough i have found someone who has tried the method that is very similar to the one that Jon has mentioned and also very similar to my situation Here This method seems to work.
Each forum I have been to will show a different method. I can't choose all of them and I don't want to choose none. Eventually I will have to take the plunge.
This way seems a fairly easy, relatively low cost solution. All the stuff (apart from the Green Glue) can be bought from B&Q or Wickes. It appears that there is no guarantee that any particular soundproofing will work as each room will be different. I have vast amounts of experience of things that don't work so I am not new to this concept lol So I'll try this way first and see what happens

Thanks again

[MarkP80]

Let us know how you get on - and don't forget the pics!

Cheers,
MarkP

[Jon Boy]

Also dont forget the pics of yourself throwing your hammer across the lounge, the kids dancing around in the rockwool and the dog taking a dump o top of your plasteboards

Jon