Sound insulating a party wall in a bedroom

[Fishwalker]

Hi,

I am getting together details of where to source materials in Hull for creating a stud wall, right against the existing wallpapered/plastered brick wall of our bedroom mid terrace party wall, due to the fact that the neighbour is easily heard at times and we want a better feeling of our home being our own.

It is a 100 yr old property and I was going to tackle removing the old skirting boards from the wall. Prob is we've made the mistake of sanding the floor and finishing it, a couple of years ago (without insulation underneath regretfully soundwise) and we installed beading onto the scrappy old skirting to finish it, not really thinking about decorating the walls further (magnolia). Now I've finally got my dream sofabed and am creating a chill out/study room, I've realised that it really needs coving installing all round before I wallpaper the fireplace feature wall, as I have period features.

I'm therefore looking at buying the required metal studwork and rockwool panels + plasterboard for the stud wall job and was going to remove the skirting first but the skirting is really painted and nailed on with galvanised 5mm thick 3" nails (discovered on a small bit of board near the fireplace that took a lot of back breaking crowbaring to get off as it was) and this walls skirting I'm about to tackle, is probably held in place by skirting from the adjoining wall, which I don't want to remove, as a radiator is on that wall and it will just take forever + we are 1st time home owners.

So... Do you think it will be ok to just set the head and sole plate of the metal studs in front of the skirting board and build the stud wall over them? I thought of placing wooden battens behind the metal stud rails (vertical) to hold them the couple of inch's needed away from the wall that the skirting will require.

I then plan to have the 400mm - 600mm distance between the rails for the rockwool and plasterboard (which I will cut a bit out of in the corners to snuggly fit against the existing skirting in the corners and after skimming, fit new skirting boards and coving. What do you think?

If I do need to remove a bit of skirting from the corner of the wall that has the radiator on it, I will need to cut it off in situ and I don't know what power tool I'd need to hire for that.

This project is on a 11' 2" (3.4m) wide wall x 8' 10 (2.46m) high ceiling.

 

[DAZB]

Yes, building in front of the existing skirting is fine but do not put any timber behind the uprights or have the footplate touching the skirting as noise will 'travel' through. Build it an inch or so in front and also caulk the perimeter once boarded prior to skimming to seal any gaps.

 

[flameport]

If you need to cut the skirting in situ, then get one of these: http://www.toolstation.com/shop/p28253 or something similar.

Fitting around the existing skirting is fine, although why metal studwork?
As above, the new wall must NOT touch the existing one, otherwise it won't be much use at reducing noise.

If the floor joists go into the party wall (i.e. the floorboards are parallel to the wall), then you really should take up the floorboard closest to the wall and fill any gaps around the joists with mastic, as this is a likely place for sound to pass between the two properties.

For the 'rockwool' to have any real effect on sound transmission, this should be high density slabs, preferably 80kg/m3 or above. The type sold as loft insulation in rolls will be useless.
High density plasterboard as well.

 

[Fishwalker]

Thanks for the input both of you! I thought metal studwork, as that seems to be the recommended thing on diy sites as they are straight with gaps to drill to the wall over wood but do you think wood then?

Our floorboards run at 90 degrees to the wall in question with joists front to back of house, however I think you have a major point about sound coming through floor boards as we do have bare boards in that room now since sanding and staining them a couple of years ago but even when we had carpet and underlay down, you could hear my neighbour.

My other half is reluctant to cut them up now to insulate or look to see if there are gaps going into next door but do you think its more important sorting this out them building the wall? I mean would fixing that be a job for the amateur? I have this wkend off work and was just about to set off to Jewsons or Wickes for supplies but now I'm having second thoughts.

We have a ToolStation in Hull so will get a floorboard saw. They look good. Have had trouble though finding a saw to fit behind a half yanked off skirting to cut through skirting nails though, hence wanting to build over them. I picked up a tiny junior hacksaw but it wouldn't cut through the galvanisned steal 5mm nails that someone's put in. It just blunted the blade.

 

[mointainwalker]

It's quite likely that there wil be significant gaps around the joist-ends, so if you are serious about the noise reduction, you do need to lift the boards and block these gaps. Otherwise the noise will just travel under the boards and into the room, not going through your new wall at all.

 

[Fishwalker]

Floor and wall in question

• Fishwalker
• 6 Aug 2011
• 1

This is my wall/floorboards. There is a cut along 2 planks that someone once took up props for central heating but we nailed these well down before we did the floor with the drum sander and we would wreak them gouging the nails out now.

I had one idea though so tell me what you think? Remove the skirting (with crow/wrecking bar and saw through nails - a task in itself!) then where there will be about an inch of old floor board, drill a hole about the size of a 5p a few times along the wall and then squirt expanding foam or other product (you recommend) through to cavity below, that would hopefully be not too wide as a floor joist would run parallel to the wall. Would this provide any sort of help to the situation before then building my wall with either CLS wood or metal studwork and compressed rockwool board + plasterboard?

I could at least shine a tourch down there first to see if I can see how big the gap would be.

 

[Fishwalker]

Well no reply yet to idea above but may have to shelve this whole project anyway as was looking for joists in the ceiling for the head plate and realised its been hidden by a false ceiling of plasterboard, which I actually knew was there as you can see the seams of the boards if you look closely. Anywhere I tap near to the wall is just hollow. As this is the case, is the false wall idea out? Can I put one up without a head rail?

Might just cove the room and get on wit the wall paper if not.

 

[mointainwalker]

Your idea is not the best, but it is difficult to say how (in)effective it would be.

The best characteristic for sound reduction is mass ( sand used to be popular) and foam is very light, so whilst it may seal some gaps which would be an improvement, some noise would still come through.

Perhaps more importantly though, in your proposed usage the foam is completely uncontrollable and will expand everywhere. You may find it coming out of undiscovered holes in your wall - or worse, it could all blow out into your neighbour's living area.

 

[Fishwalker]

Fair enough then! Was just an idea. Ok so any thoughts anyone on screwing woodern battens directly to the brick wall at the top and bottom (not touching floor) and then screwing vertical rails of wood to these with some bits of wood supporting in the middle? This is cos of the lack of joists in the ceiling due to false ceiling? I really would like to make a start today but this wkend is rapidly coming to a close and i'm working all next wkend. If I could at least start on the skirtings and buy some materials today...

 

[Fishwalker]

Oh... by the way mointainwalker... back to that theory of mine and the putting a few holes behind skirting in the floorboards to see below ...or lifting the 2 bits of board I could prise up which are fairly close the the wall to the left. If I bought a bag of sand and poured that between the joist nearest the wall and the wall and spread it out along said wall, do you think that might be a way to go?

 

[Fishwalker]

Ok just re-read replies above and see I can't screw wooden uprights directly to brick wall, but this is my problem. WHat if I fit strips of rubber between the top and bottom wooden rail running horizontally along wall and use rubber washers? Will that be ok?

 

[cajar]

I think if you can avoid contact with the wall then it will always be better than using rubber washer because they will transmit some sound. Seems like the best option might be a stud wall a couple of inches out.

I would personally start with finding and filling gaps below the floorboards as it's very likely fixing these alone might negate the need to build a wall.

 

[mointainwalker]

Use any rubber strips against the ceiling rather than the the party wall

Forget the sand , that was an illustration to earlier methods

 

[HH1]

Try soundstop.co.uk for ideas/solutions/materials :-

http://www.soundstop.co.uk/

 

[Fishwalker]

Hi again...

Back on this subject once more, as I have not done anything since I last wrote because the whole thing just got too confusing and big...

Today the new lot of students moved in to the other house next door on the party wall opposite to the one I've so far talked about, on which you have the fireplace, an alcove and a cupboard in the righthand alcove.

It basically got me annoyed again and I've been staring at the alcove wall where the sound seems to be coming through.

The problem is and I didn't really get a direct reply from before... There are no joists we can screw a head plate too in the ceiling, due to the false boarded ceiling. You tap it and it sounds like hollow plasterboard right out from the wall along the ceiling.

Therefore, can I put wooden or metal rails vertically down the wall on either side of the alcove, an inch or so out and attach struts horizontally going top to bottom instead and then insert the compacted insulation board mineral wool and cover with soundproof backed plasterboard? I also have half a chance at removing the skirting in that small alcove area too?

And about the floor boards. I really can't pull them up, it's just not viable with the amount of time and money we spent on filling, staining and varnishing them. Can't see any other way to solve sound leaks ther unless we carpet over and the floor looks great.