what % difference between a 2" & 4" stud

hello well my build is continuing... we've hacked of render and filled a skip and vandexed the walls for damp... removed RSJs from the ceiling... removed a very old ceiling and now I'm starting the long road to making good : )))) my question is this I have a door in the corner of the room which opens against a wall I want to stud and leaf. If I use 4" depth studs and 4" depth rockwool my door will be very narrow, if I use 2" studs and rockwool, my door will be a little bit bigger! The wall goes onto my neighbour's kitchen so I want to make sure it's well soundproofed. How much difference is an extra 2" of air and rockwool in the wall going to make. Please reply in simple terms, ie 20% / a little bit etc, I don't really understand all the acoustic measurement lingo : ) question 2 we need to install gas (not for the studio) and the pipe may run through the studio and through the wall into my kitchen. Will this severely compromise my soundproofing, even if I use acoustic caulk around the pipe where it goes into the wall? I'm thinking of prisoners tapping messages to each other at night on pipes! Pic attached of my wall, suggestions welcome. 2" or 4"...

I would say that 2" vs. 4" is a big difference. The width of the air gap between leaves is a significant part of the mass-air-mass equation. Besides, I would not want to hang anything on a 2" stud! :shock: I would think that the gas line, if it is firmly attached to both leaves, will be a significant detriment to your isolation outcome. If your building codes allow for it, you may have to use specially designed neoprene grommets or something. Don't underestimate the importance of this design obstacle -- you are right to ask about it.

in terms of strength I was considering using the 4"x2" on its side flat on the wall ie it would a 4" face and be 2" deep, but I guess I'll have to put up with a very narror door if it's as you say! i also have radiator pipes coming in on one wall for a wall mount radiator - any tips on dealing with this pipework? What are neoprene grommets ? Where might I find more info on this? Thanks Sharward ;)

Check out Mason Industries' Type SPS Spool Type Acoustical Pipe Seals. Note that there is an Exclusive UK agent for Mason Industries Inc. that may be able to get the product for you locally. Mason Industries has some of the most impressive acoustic isolation products I have seen, but their Web sites are disgustingly bad. --Keith :mrgreen:

cheers keith anyone else got any opinions in the 2" vs 4"?

Based on double 1/2" gyp both sides, a 2" air/insulation space will cost you about 2 dB at the low end and about 1 dB in the mid/high frequency range; again, don't pay for rockwool inside a wall unless every last dB counts; it'll ALMOST be noticeable in most cases, but NOT worth 3x the cost... Steve

anyone want to buy some rockwool in Bristol? :(

I'm NOT saying the rockwool won't work inside walls/ceilings; only that it's just a TINY bit better there than the cheaper, fluffy fiberglass. Also, you may need quite a bit of that for in-room acoustic treatments with your low ceilings, etc - in those places, the lighter stuff does pretty close to NOTHING... Steve

hey - you remember my previous posts! maybe I should make a studio build thread rather than keep posting individual questions... what's the protocol round here? not sure if my conversion is hardcore enough to warrant a thread, as it's just converting a room in my house... re acoustic traps I've bought plenty of rockwool , and have enough for the ceiling and two walls which leaves 24 slabs for acoustic treatment, some 50mm some 100mm - infact it's very hard to move in my house at the moment for bloody rockwool ! : ) thanks for the tips sir

lubaloo wrote:

hey - you remember my previous posts! maybe I should make a studio build thread rather than keep posting individual questions...

I personally think that works a lot better, since often questions get slightly different answers within the context of one's overall project. For example, in a "which is better, this or that" scenario, the answer may be "Don't do either one in your situation, because _______... Consider doing _______ instead." I remember last year there was one project that was splintered among dozens of threads started by the person. It was impossible for me to follow. I admit to starting new threads sometimes though, at times that it seem to make sense. So, I'm a bit of a hypocrite! :lol: Anyway, that's my two cents... :) --Keith :mrgreen: