I would keep that to myself if I were you.

.. Although, at 4mm you don't really have a choice.

I went to see a mate a while ago… He proudly showed me his new shed… which he had partly wired up himself… It was a second hand shed and someone had already fitted it with a double socket on each wall. When I looked, he had…

Used 2.5 twin and earth to wire it in which had a 13 amp plug on BOTH ends (to be clear, the end in the house AND in the shed has a plug on)

The cable went through the double house wall; un protected, and was plugged into a socket on the wall.

The cable was clipped to an outside wall for 5 meters, then along the TOP of a wall for another 2 meters, along the side of 3 wooden fence panels for 4 meters, and finally, across to the shed in mid-air at a height of 1.5 meters, for 4 meters, unsupported!

Once in the shed he had put a plug on the end of the cable and had it plugged into one of the sockets!

I asked him why he had not wired it in to one of the sockets directly and he said “he was not good with electrics” no kidding! When asked why he had used twin and earth, he said “that’s what the man at B&Q said to use”

Back on subject… I noted the comments about security and to be honest, the motor on its own holding the door closed was not secure. I have therefore modified the mechanism so that before the motor pulls the door up, it pulls a cable which works two BIG side latches. I know they do a latching kit, but this is a none standard fitment as the motor is set well to one side of the door as I have a hoist in the middle of the garage. I didn’t want to reduce the headroom above it.

Here is a clip of how it works…

Thanks again for the advice guys.

Used 2.5 twin and earth to wire it in which had a 13 amp plug on BOTH ends (to be clear, the end in the house AND in the shed has a plug on)

 

This is scarily a common thing I've seen.

 

The other is on narrowboats where an inverter is fitted that makes the outside (male) 3 pin industrial socket live when floating along...