Connecting electrics:
After sorting out the wiring layout, all that was needed was to connect the system up. I double checked the basic cable routing first to make sure that everything can be concealed nicely. The light switch cable was altered but generally the rest stayed as originally fed. The fan spur circuit was connected first. The supply was fed directly from the back of an existing socket, the closest one to the joining conduit in the garage. This then fed the isolator switch on the left and then to the speed controller on the right, both on the left hand side inside the 'airlock'. You'll notice from the photos that I currently have the speed controller attached (temporarily) within its supplied surface mount box but this will be recess mounted eventually - I didn't have a back box deep enough so I need to get down to ScrewFix again.
The studio lighting circuit was then fed directly from the garage consumer unit along with the two 2.5mm T&E cables for the studio ring. I attached some timber to the garage wall to run the three cables into the top of the consumer unit (this helped to ensure the cable clips were held tight against the cables - breeze block is a bit soft and prone to small nails pulling out). Once attached, the cables were easily tacked down and fed through the top of the consumer unit...obviously completely isolating it from the supply first!! I connected up the ring first with a temporary single socket in the studio where the main studio sockets will live. This completes the ring circuit for now though this will be replaced by my dado trunking reused from my old setup. This also gives me a handy supply along with the two 2-gangs in the 'airlock' to continue the build. I had to take a feed from the garage up until now. All checked and worked.
To get the lighting circuit up and running I cut a hole in two lengths of timber and attached a halogen to each. These were slotted between joists, above the drywall recess timbers (photo describes this better). Only temporary but at least gives me some light and allows me to connect the lighting circuit up safely.
Last thing: Got up into the house lower loft. Identified where the existing outbuilding supply is fed (conveniently via a junction box). Isolated the household supply, removed this single T&E from the junction box. Attached my length of CAT5 inside the studio and pulled the T&E through into the loft and along with it my CAT5. Not exactly sure how I'm going to be connecting this but I have the cable link now so I can deal with that later. I've now completely removed the last of the original wiring that was in there when I first started!! >>photos<<