[Dipman]

Hi,
I'm thinking of soundproofing the celing of my cinema room. I'm about to get a bedroom built above it for my new daughter ( no upgrading in the near future!) and want to try and minimise the noise.

I've thought of buying her earplugs but the wife insists on a different solution.

I was thinking of laying 30mm rockwool slabs across the rafters so that when the bedroom floor is fitted I will have a 'sandwich' of plasterboard celing, insulation, rockwool slab then floorboards.

Anyone tried this, will it work and does anyone have any other ideas which may help?

[Gary Lightfoot]

You could cut and fit two layers of the 30mm high density slabs tightly into the floor joists of the bedroom to be, then fit the floorboards back. The joins of the second layer to overlap the joins of the first. Seal all the floor board gaps with silicon rubber, including the edges by the walls (before fitting the skirting perhaps), then fit a heavy duty underlay before laying the carpet.

That's probably what I'd do, plus I might fit some ordinary 4inch rockwool over the HD slabs so ther'll be only a small gap between the floor boards and insulation underneath.

Another idea would be to cut and fit some lengths of plasterboard between the joists onto the ceiling from the bedroom above using no more nails to ensure nothing rattles or resonates, then use the HD slabs. The extra mass may help with bass transmission, which will be your biggest problem I would think.

Gary.

[deckard]

Have a look here for some further ideas.

I use their Studiofoam products within my room (and they're very good), but as they state on the link, those don't help stop sound transmission, only their products on the page I've linked to will help.

Otherwise the suggestions already made sound pretty good.

[Dipman]

Thanks guys, both good ideas, I think you're right Gary the bass would be the biggest problem. That stuff looks good deckard any idea of prices, the uk distributers site is under construction.

I take it what i need to do is provide 'mass' to deaden the sound rather than leaving air gaps in between layers?

[Gary Lightfoot]

That sounds about right. You could fit a complete new layer of plasterboard to the ceiling underneath which might work a bit better than the strips inbetween joists, but all the time you're connected, the bass will get through..

Gary.

[Dipman]

Thanks gary , Ithink I'll give your ideas a try and depending on the prices for the Aurilex material I might incorperate that as well!

[deckard]

Have a look at these sites for some ideas on pricing:

http://www.studiospares.com/viewprod...TION&p=1&gid=6

http://www.dolphinmusic.co.uk/d2/?pa...9ec06aafc6677c

[Dipman]

Thanks Deckard,
I'm pleased I have a couple of months to save up or an additional mortgage might be needed!

All sound advice from the above. In essence you want to acoustically seperate the two rooms. As such you should treat the ceiling the same way a builder would if building flats, thus look to the building regulations new part E sound transmission, there's loads of stuff on the web, heres an example
http://www.customaudiodesigns.co.uk/articles/bregs.htm
http://www.stratford.gov.uk/stratfor...E%20Guide.pdf/$File/Approved%20Document%20E%20Guide.pdf

In addition to this a really usefull book with good diagrams of what to do is The Building regs Explained and Illustrated.

What you should try and do is seperate the ceiling plasterboard from the body of the floor and have continuous insulation between. I.e. an indepandantly supported ceiling, add joist inbetween the existing floor joists, they don't need to be the saqme size as they only support the ceiling. Then weave the insulation between the upper and lower joists. The void left between insulation and floor boards above is not crucial as the sound will stop at the insulation. But sealing the joints against the wall is. A reasonable job will get say 45db redustion a very good job may get as high as 60db.

[Gary Lightfoot]

Hi Bruno,

great links - thanks.

Gary.

[happychappy]

Originally posted by Dipman
Thanks Deckard,
I'm pleased I have a couple of months to save up or an additional mortgage might be needed!

I went for the "fill as full of rockwool as possible "route (the ceiling void that is) and sound per pound it wasnt a bad choice as it does quieten down the sound quite a lot but to get anywhere near total silence would cost a fortune as with everything its horses for courses the rockwall route also leaves a little over for some more D.V.D.s.
Good luck

[Dipman]

Bruno,
I'll second Gary lots of good info thanks for the links!