John Sayers' Recording Studio Design Forum Archive

Thanks again for the input.I should have mentioned that the works have been approved by structural engineers and I do have an architect .However Ive found it really difficult to get specific advice on soundproofing.My main concern is to achieve isolation between my rooms.The floor below is for storage,however the floor above is office space which is also being renovated. I know the inherent dangers in taking advice from internet sites especially those with financial motives.I have been looking again at the BBC pdf from thier R&D dept."Lightweight partitions having improved low frequency sound insulations".(see attachment)
As I already have 3x2 partitions lined with rockwool in place I had thought of doing a variant of fig 11(d). My existing walls are filled with rockwool however 11d is an air space.In answer to your query I will be building a room within room each side of the existing partitions.Should I go with plan as in sketch attached.Also where I intend to build new walls should I copy 11d leaving out rockwool infill in centre wall.

If you have an existing wall between the 2 studio rooms, and that wall is about where you want the final wall to be (looks from the sketch like you're adding a wall on each side), and the floor of at least one of the rooms will be floated, then IMO you're spending a lot of money that might not be doing you as much good.

If it's within your budget to do this, that's fine. If you need this much sound isolation, IMHO you'd be better off building one of the new walls on one side out of concrete block- you'd be spending less money.

If what you're after is a working-level of sound isolation (as opposed to a wall that can keep the sound of a jet engine from leaking thru) you might be better off just taking the gyp board off of one side of that existing wall, and building a second wall on that side and covering only the outside with gyp board. If you're trying to add mass to the wall, just slap another layer of gyp board or MDF to each side (the more different thicknesses and densities in the wall, the less chance of a resonant frequency making it thru).

The wall section you've sketched out has 4 leaves between the studios. The extra mass is doing some good, but it's not nearly as cost-effective as putting it all into 2 leaves with an air spring between them.

Another thing you could do- leave off the extra studs you were planning to buy, and add 2 new layers to studio A side, then on studio B side you could add one layer, then strap resilient channels to it's face (screwed thru into the stud) and then put one last layer over the channels.

*shrug* lots of options. The one you suggested will work, but it's a bit wasteful of materials and floor space.

Good luck!

Kase
www.minemusic.net

No big deal, very few posters give enough info the first time around -

I'm glad you have engineering help on this - that way you can check any ideas we throw out there with your engineer/architect for structural.

Kase gave you good advice on wall construction already - the most efficient use of wall space is using only two leaves of mass with only one air/insulation space (BBC uses the term "leaf" to mean an entire wall frame with wallboard on both sides, NOT what I mean)

I'll try to catch up on this in a day or two, when I'll also combine your two threads - please don't start a new thread for each post in future, it only confuses things (me, mostly) and slows me down when re-capping in order to give best advice I can.

Meantime, there is a wall graphic on one of Ozzie's posts recently that shows an STC 63 wall construction - this is one of the most efficient ways to build walls.

More later... Steve