Soundproofing between ground and first floor

gaelicyoda

Hi All,

I've seen a number of soundproofing threads in here, but mostly dealing with party walls and noisy neighbours.

We've bought a house with a standard joist and ply floor between the first and second floors, and I'm trying to figure out the most cost-effective way to go about dampening sound between the floors.

The engineer I had out to the house showed me a little test while he was out inspecting the house - he stayed upstairs while I went directly below him and he dropped a €2 coin on the floor from an outstretched arm. Suffice it to say, I was pretty shocked by how much the sound carries. Now, I realise that once there's flooring down and curtins up, etc. to break up the echo in the rooms (they're totally empty, just plastered), it will be a little better, but I can't imagine by much.

A few tradesmen I've had around have suggested putting a layer of plasterboard down on the existing ply, with another layer of ply on top of that again. Has anyone tried this, and if so, did you find it good?

Cheers,
GY

gman2k

I suggest you do a search of this forum, as there are plenty of threads on this.
However, briefly, there are two types of sound transmission - direct through materials, and airborne.
There are different techniques to deal with both types.

Leadership

How much sound do you want to eliminate and how much do you want to spend? I have lived in houses like that for years and found a number of solutions help but the costs can creep up. BTW a layerof plaster board will not help that much.

DOCARCH

Google 'gypfloor silent'.

That's your best bet for an existing timber floor structure. For a domestic dwelling you do not need to use system to underside of the floor, just on top. This system reduces both impact and airborne sound.

gaelicyoda

Thanks guys:

Leadership wrote: »

How much sound do you want to eliminate and how much do you want to spend? I have lived in houses like that for years and found a number of solutions help but the costs can creep up. BTW a layerof plaster board will not help that much.

I appreciate your feedback very much, so I don't mean to be trite here when I say this (and please don't take this up wrong), but as much as possible for as little as possible. Can you maybe outline some of the solutions you've come up with - perhaps assigning each an effectiveness, cost and value-for-money rating? My gut feeling on the plasterboard was that it would be fairly crap alright, but always good to ask around.

DOCARCH wrote: »

Google 'gypfloor silent'.

That's your best bet for an existing timber floor structure. For a domestic dwelling you do not need to use system to underside of the floor, just on top. This system reduces both impact and airborne sound.

Thanks a million Docarch - I've had a look at the technical document for this, and it looks good, I just wonder how expensive... it looks like there's a supplier in Dublin, so should be able to find out easy enough.

Cheers,
GY

gears

Another option for googleing would be "Phonewell". It's another sound dampening board.

gaelicyoda

gears wrote: »

Another option for googleing would be "Phonewell". It's another sound dampening board.

Thanks gears, I'll check it out.

Cheers,
GY

Leadership

Here are my previous solutions:

Carpet - Nice thick carpet, this reduced the walking, dropping noise and also damped other sounds. Sound still carried through stud walls etc but this fairly acceptable. This was cheapest most cost effective

Rubber underlay (wooden floor) - This was a 50mm thick underlay that I used, not as good as carpet but did reduce noise. It was fine without kids but still was loud when the partner was getting ready to out and was pacing around in her high heals.

Screed/underlay - This was a great almost as good as big thick carpet. I layed a 10mm acoistic underlay followed by 50mm screed. Again this gave us the floor finish we wanted (wooden) and reduced the high heals pacing noise. Even kids jumping around worked.

All of the above require stud wall accoustic damping to fully work I found.

Best solution - Build a new home with concrete floors and internal block walls This is my current solution and easily the best. I gave up on timber homes a number of years ago due to the sound.

gaelicyoda

Leadership wrote: »

Carpet - Nice thick carpet, this reduced the walking, dropping noise and also damped other sounds. Sound still carried through stud walls etc but this fairly acceptable. This was cheapest most cost effective

We'll be putting carpets in the bedrooms upstairs alright , so really I suppose it's just the landing (wood), en-suites (tile) and bathroom (tile) that will be the main problem areas.

Leadership wrote: »

Rubber underlay (wooden floor) - This was a 50mm thick underlay that I used, not as good as carpet but did reduce noise. It was fine without kids but still was loud when the partner was getting ready to out and was pacing around in her high heals.

I think this will probably be the route we'll go for the wood floor on the landing. At that thickness, was there any give/movement in the floor? I wonder if you can double-up on it?

Leadership wrote: »

Screed/underlay - This was a great almost as good as big thick carpet. I layed a 10mm acoistic underlay followed by 50mm screed. Again this gave us the floor finish we wanted (wooden) and reduced the high heals pacing noise. Even kids jumping around worked.

I hadn't even thought of using screed actually. Just packed sand or cement? What if you need to get into the floor cavity at some stage (to repair a light or something). Bit painful to tear up and replace I'd imagine?

Leadership wrote: »

All of the above require stud wall accoustic damping to fully work I found.

This is where we'll really be falling down I think - all the upstairs stud walls are already fully plastered and finished, so I really don't want to think about tearing up the walls and replacing them again. Unless there's a way to do this with minimal disruption? (which I doubt there is)

Leadership wrote: »

Best solution - Build a new home with concrete floors and internal block walls This is my current solution and easily the best. I gave up on timber homes a number of years ago due to the sound.

This would be my preference too, but alas, that's not what we've got to work with!


Thanks for all your suggestions Leadership, I really appreciate it!

Cheers,
GY

whowantstwoknow

DOCARCH wrote: »

Google 'gypfloor silent'.

That's your best bet for an existing timber floor structure. For a domestic dwelling you do not need to use system to underside of the floor, just on top. This system reduces both impact and airborne sound.

I'm looking into this system for a noise issue between kitchen and bedrooms. Primarily its the noise from the kitchen to the bedrooms, but any reduction the other way more the better. I wont be altering the kitchen ceiling from below (disturbance, cost etc..) but intend to fill the void with the mineral wool, the strips on the top and the gysum plank etc. I read the wool is 100mm, is this enough or rather any need to add more? Should I verify with an engineer to confirm the current joists can take the additional load of this solution?

In terms of noise, should I re-use the floorboards or install plywood. Conscious that this solution raises the floor by 7mm but would there be any additional advantage of laying an underlay rubber mat of sort before the final floor finish?

Thanks for any assistance

W.