Chief sparky Peter Briggs (also known as Balo) takes us through the process…
Checking the cables
The first job is to check that all the cables have been pulled through the plaster and are in the right place. We used our drawings for this, the ones David marked out with the exact measurements at the end of the first fix, often referred to as 'built drawings'. This should show exactly where all the cables are located.
We thought that the plasterers had accidentally buried a couple of spotlight cables in the bathroom ceiling. We consulted David's drawing, but were none the wiser. He'd missed them out. So we were looking at a blank ceiling with no idea where the cables were. In this case we had to go back to the original drawings where the light fittings were marked and just hope that our cables were in the same position.
Fishing
To find the cables in the bathroom ceiling we used a cable with a hook at the end. This is what we call 'fishing'. Unfortunately the crossbeams got in the way so it took longer than expected. Another cable had been buried in the lounge, but David fished that one out much quicker and he was delighted.
Last-minute adjustments
Often there are adjustments that need to be made at this point to accommodate other tradesmen. In the Bricking It bathroom, for example, the towel rail had been moved 18 inches from its original location. Since we had already done the wiring we had to run the cable to the new position.
This may sound easy, but every 400mm there was a metal upright in the wall, as well as a timber in the way too, so we couldn't get the cable through at first.
The solution was to cut out a piece of the plasterboard wall, drill through the metal uprights and timber, and install a conduit (a tube) to feed the cable through. A change like this may not seem like much but it can take one electrician one day to complete.
Earthing
The main incoming water pipes need to be earthed with cross-bonding which links together the pipes in the bathroom, kitchen and anywhere the electrics and pipework meet. The metal bath and kitchen sink have to be earthed too.
It's important to be aware of the rules about electrical safety in bathrooms and shower-rooms. Obviously you don't want someone in the bath operating a light switch.
David and Greg Males had the main bedroom for the second fix. They put in a metal backbox, but forgot to earth it. Without correct earth connections the circuit will still work but it is unsafe and the safety devices may not operate quickly enough to avoid a shock. It's one of many things Balo will check.
Connecting up
This is when we make the connections eg socket tops, the fuse board, light switches and some light fittings. Spotlight junction boxes go in, but not the down lighters and lights themselves. They'd only get covered in paint during the decoration.
Constant checking is crucial at this point. All the connections need to be good. If there is just one bad connection, it'll blow out. The live connections are obviously important, but the earths are important too because if something goes wrong it's the earth that will protect you.
Now the flat is nearly complete. Sockets are left loose and covered with plastic to protect them from paint. The electricity is ready to be turned on.
Electrical work can be very dangerous. Always consult with a qualified electrician before carrying out DIY work at home.
