So the time has come to stop designing and start building! First off, the floor. It's going to be a standard stud type floor, with the timber battens lined with some resilient floor tape. The floor will be 40mm away from the main wall. At the corners of the structure will be extended battens that will ensure the structure does not move when complete. The battens will be separated by 400mm and then 22mm floorboards will be laid on the top. Rockwool RWA45 will be laid in between the battens. I've opted for the 100mm option for maximum sound absorption. I'm in the process of ordering 20 packs of Rockwool from CCF. Best price I have found and free delivery over £200. I'm also getting the floor tape from Custom Audio Designs. They're really good at giving advice, and their website has loads of very useful information. Gonna get some acoustic sealant from them too, stuff that is similar to Green Glue.
So here's how the floor should be looking when done :
Hopefully the next post will be the build :)