John Sayers' Recording Studio Design Forum Archive

Hi

My builders are using a wallboard 12mm plasterboard with 18mm polystyrene on the back.

Based on the theory that sound doesn't like passing through different
materials I thought it might be better than 2 standard wallboards of 12mm. Also the resonance of each material would be different.

What do you think.

Not sure without more info - got a link or anything? Steve

Now you metioned it I started looking for specs and asked my builder exactly which board he was using, here is the spec for the board

http://www.british-gypsum.com/PDF/TI-05 ... 0BASIC.pdf

Its a thermal board and I have now found that british gyproc also manufacture acoustic boards, they have three boards available
soundbloc , soundbloc RAPID and soundbloc RAPID MR. question is which one to go for, I am thinking that these must be better than the thermal board he is currently using.

The website is http://www.british-gypsum.com/

here is an execellent link to the british gypsum white book there is loads of info available and the attenuation of several methods of installation are clearly explained.

http://www.british-gypsum.com/immediacy-217

The R rating for the soundbloc boards are 0.06 m2K/W
However the R rating for the 30mm Thermal board is
0.55 m2K/W so is the larger number better or worse ?

I am guessing that the 30mm thermal board is better than a 12.5 mm
soundbloc board which is not suprising as its 17.5mm thicker.

As I'm going up against an existing wall I'm thinking it may be a reasonable solution is I pack some acoustic wool behind it as well.

Does this seem ok.

0hz wrote:The R rating for the soundbloc boards are 0.06 m2K/W
However the R rating for the 30mm Thermal board is
0.55 m2K/W so is the larger number better or worse ?

I am guessing that the 30mm thermal board is better than a 12.5 mm
soundbloc board which is not suprising as its 17.5mm thicker.

0hz,

well you're guessing wrong.

The thermal board is thicker - and has a better R value - but it has less mass.

It's a gypsum product bonded to a foam backing - so although it has good thermal values - it has poor sound isolation values.

What matters with sound isolation is mass - not thickness per-se.

You would be better off with the soundbloc....... although you can acheive the same isolation in the end by using standard sheetrock.......

Rod

Thanks guys, I've been thinking about it and you are right. Its got to be soundbloc.

"Its got to be soundbloc" - not necessarily - I know from dealing with other UK members that your pricing for gypsum is about 6 times as high as I pay for it, but what's the cost of this special "soundboard" stuff? Some of these "special" materials are 'way overpriced compared to standard materials, and without much (if any) gain in performance.

Can you post a price comparison between the soundblock stuff and normal gypsum in your area? Thanks... Steve

Its a good point, I'll try and get some figures. It would be good if it were possible to work out the cost per DB of attenuation/metre of any given method.
Because its fairly specialist your at the mercy of contractors and suppliers.
Although these days building regulations may also include sound isolation specifications, for instance in hotels,hospitals, and appartments so it is getting slightly better here in the UK.

My build has been specified utilising high density blocks, I have an adjoining wall between the studio and kitchen, and it has been built with two walls using these blocks, it would be interesting to cost this method against using a specialist stud wall which I know would could achieve around 55-60dB of attenuation, I don't really know what the attenuation of my two walls will yield but I am expecting something around 45-50 dB, in my case hanging kitchen cuboards off a stud wall would be a little tricky. In the end it will be a compromise as its a home studio which has to be lived in as well, and of course space is always a premium.

I/we have decided to use the 30mm Thermal board to line the studio but also add 12mm soundbloc board on top as well, in conjuction with the high density blocks this should give me enough attenuation to keep my neighbours happy.

cpsupplies.co.uk

price shown for 1200x2700 board

12.5mm soundbloc works out at around 21.13 GBP or approx 38 - 39 USD

standard board same size is about 13.73 GBP or appros 25 USD

difference is quite considerable !

Yeah, specially when you add up how many pieces it takes - here in the US, 1200 x 2400mm gypsum in 15mm runs around $5.60 USD each, but the specialty boards can run 5 times that amount. Soooo NOT worth it... Steve