Ok so I am not 100% on getting the best isolation possible without spending the Earth.
When the shell is up I will have a single skin 6" concrete wall on all 4 sides, my plan was to build a room within a room.
Originally we had decided on one stone wall but for various reasons it wasn't practical so settled on one end wall made from RPG Diffusorblox sat on this, SWW Masonry Isolation - Mason UK - Acoustic Engineers
The other 3 walls will be 6" x 2" timber inside out walls with 2 sheets of plasterboard facing the cavity, we plan to do this so the acoustic treatment sits between the studs to save space. I planned to sit them on this, W Pad - Mason UK - Acoustic Engineers
Most of the walls will have 4" of RW3 with a 2" air gap behind and cloth and wooden slats over the front. I have also come up with a novel diffusor panel made from oak offcuts they sell as firewood. I will try to get a picture up today.
I intend to sit 9" x 2" purlins on the 2 side walls just under the current roof, again an inside out design so the acoustic treatment can fit betweeen the purlins. On the lower parts of the ceiling (anything below 12' or so) we intend to use 3" DIY Space Couplers, 3" RW3 and a 3" air gap behind which will fit perfectly betweeen the purlings. I have bought some bamboo sheets to make the couplers, I did try a couple of prototypes over here, SPACE COUPLERS. Theory, construction and effectiveness on traps.
The higher part of the ceiling will either be left as plastered with exposed purlings or perhaps have some poly diffusors installed. I haven't quite decided on that yet.
I then planned to float a 20mm toungue and groove floor with 20mm oak bonded to it and use this underneath, http://www.rpginc.com/PDFs/Isolation...20profile).pdf
So is this a good plan?
Is there a better or maybe cheaper way of achieving the same result?
Any potential pitfalls to watch out for?
All suggestions and feedback welcome.