Nail through electric cable

heppy23

trying to finish the flor in my sons room before the carpet comes on Wednesday.

I have been going round securing any loose floorboards (old house) and of course I've gone and put a nail through the electrical cable.

The electricity tripped out and I've got it back on but have removed the fuse for the upstairs circuit is.

The wire is blackened round where the nail went through it. I presume it would be dangerous to put the fuse back in and hope it's OK.

On the basis that the wire is damage could I just cut out a section and put a new bit in with some junction boxes? Or should I get an electrician out?

Do those mains wire detectors work well? Would they have stopped me doing what I just did?

Valley's_girl

Hi I am sorry I don't have any advice I can give you but I am sure someone will be along shortly who will be able to help.
Ally x

andrew-b

The metal/cable detectors are well worth spending a tenner or so on! You are correct in isolating the affected circuit...but do check you've isolated the right circuit!
Replacing a damaged cable doesn't come under part P so you can do it yourself if you feel comfortable doing it (or know someone who could do it for you). Ideally you should replace the cable from wherever it terminates. If that isn't viable it can be repaired with 2 junctions boxes plus a new piece of cable between. If your lucky you might have enough slack in the cable to get away with one junction box - but it shouldn't be under strain If using junction boxes make sure no bare wire is visible and that the outer insulation of the cables is secured inside the junction box without being under strain. The junction boxes should be screwed down to say a joist under the floor.

Whilst you have floorboards up I would also mark on the floorboards in permanent marker or pencil the position of the cables to help avoid the same mistake again.

Andy

Incisor

heppy23 wrote: »

... of course I've gone and put a nail through the electrical cable.

The electricity tripped out and I've got it back on but have removed the fuse for the upstairs circuit is.

The wire is blackened round where the nail went through it. I presume it would be dangerous to put the fuse back in and hope it's OK.

On the basis that the wire is damage could I just cut out a section and put a new bit in with some junction boxes? Or should I get an electrician out?

Dangerous to put the fuse back in. If you are lucky and have 100mm of slack, you can just cut at the point of the fault and rejoin with a single junction box. Do not use connector blocks and tape over. Get an electrician out if you don't understand what I am saying here or if you have any doubts.

27col

Incisor is right. If there is some slack, then you can repair using a single junction box (30amp 3 terminal). If there is no slack then you require 2 Junction boxes (30amp 3 terminal)and a short length of 2.5 mm squared cable. Make sure the fuse is out or the circuit breaker is off. If you are not sure of any of the above then get someone in. I was an electrician before I retired and it is a very easy thing to damage a cable in the way you have. Did it myself once. I put three nails through the cable before I finally got one to go between the live and the earth.

heppy23

27col wrote: »

Incisor is right. If there is some slack, then you can repair using a single junction box (30amp 3 terminal). If there is no slack then you require 2 Junction boxes (30amp 3 terminal)and a short length of 2.5 mm squared cable. Make sure the fuse is out or the circuit breaker is off. If you are not sure of any of the above then get someone in. I was an electrician before I retired and it is a very easy thing to damage a cable in the way you have. Did it myself once. I put three nails through the cable before I finally got one to go between the live and the earth.

That is what I did and it worked a treat.