Can I add in a PIR to a garage curcuit?

I have a new garage with exposed wiring clipped to the beams...
Can I 'tap' into this wiring to create a new light and switch or do I have to go right back to the fuse box?

easiest is to go to the fuse box, since if the cable is clipped there will be no slack to work with (also depends on what said cable is feeding)

or maybe loop off from the ceiling rose (if there is one)?

it also depends on what size the circuit is at the moment..

if it's a socket circuit then it needs to be fused down..


to use a junction box you only need to "find" about 10mm of slack..

you strip the outer and small sections of the inner where it passes through the box and terminals respectively.. that's the beauty of those terminals.. you don't even need to cut the cables..

the pnly problem then is that the earth would be un-insulated, so you will have to cut that one and sleeve it..

just go for the JB with the terminals in a line and use one of the middle ones..