Stud Partitions vs. Brick partitions

We are a collective of sound engineers who’ve just rented a space to convert into a studio in London and wanted some advice on the renovation work that we’ve planned. The room is in an industrial complex bordered by two workshops that create negligible noise. At the back of the unit is a bunch of live/work units across an alleyway, which are all double-glazed. There is no one above and the floor is made of concrete slab. We are contemplating two types of partition to separate the control room from the live room. The wall is 20.6 foot (6.3 metres) across by 9.4 foot (2.85 metres) high 1) Build a brick wall behind the existing plasterboard partition. The air gap will be filled with rock wool and the brick wall will be plastered. 2) Build an additional plasterboard partition filled with rockwool. Both plasterboard walls plastered. We have bought two acoustic doors to use in the wall, which will be sealed using the magnets in the door and the metal in the frames. Our budget is fairly tight but we are able pay for tradesmen to do the brickwork and have experience building stud partitions. Which system would give us the best cost/isolation ratio and what kind of SRI figures can we expect assuming the walls are correctly installed. Has anyone had experience building internal brick partitions? Dimensions and pictures are included below

Easy one to answer. Brick will give better LF isolation than stud walls. SRI is not for music isolation. To get some idea of the difference have a look at fig 6, pdf page 16, in NRC IR 818 more than 29dB at low frequencies. Stud walls are lucky to get 22 dB minimum. Andre

thanks andre. I think we've decided to go with a brick or concrete block wall and to use the existing plasterboard partition separated by an airgap. we saw some 8" thick hollow concrete blocks but we were wondering what to fill them with. We thought sand might be easier than filling them with concrete. What would you advise?

cue wrote:

thanks andre. I think we've decided to go with a brick or concrete block wall and to use the existing plasterboard partition separated by an airgap. we saw some 8" thick hollow concrete blocks but we were wondering what to fill them with. We thought sand might be easier than filling them with concrete. What would you advise?

Some of those cores will need rebar and solid structural grout in order for the wall to be sound - fill the remaining cores with sand. Just make sure that you make any penetrations through the walls that you might have to make BEFORE you fill with the sand and install the running bond beam at the top of the wall - otherwise any drilling will release sand and your isolation will be for nothing. Rod