Avoiding Wires When Drilling into a Wall

coolbiking

I bought a stud detector with an AC detector on it so that I can check for wires when drilling into a wall (plasterboard) but on some walls the alarm goes off no matter where you check on it.

On one wall in particular there is a light and a plug socket but even when checking 2-4 ft away from these (not on vertical or horizontal lines to the fixtures) the alarm still goes off.

Is there a possibility that there is a huge amount of wiring behind the wall for some reason other than the fixtures seen? The house is two story but I cant see anything upstairs which would have wires running through this wall.

Any ideas on how to detect accurately whats there or drill safely?

meercat

these detectors are notoriously unreliable
as you have said the wiring should be vertical or horizontal(not guaranteed)
as its a stud wall the best bet is to drill slowly into the board and not let the bit go in too deep

a small screwdriver pushed gently into the plasterboard can do the job without the need for a drill if you are unsure,then just widen it to suit the rawl plug

Bruthal

What are you putting up on the wall

Steve

Never assume that the cowboys followed the rules - especially in a 'boom' house.

If you are drilling into plaster, drill the thickness only, no more than 15mm and poke the rest through with a screwdriver.

coolbiking

Thanks for the info lads, apologies it took so long to get back to you. Am just hanging a coat rack up.

Would you not get zapped sticking a screw driver into the hole as well though?

Steve

A drill will easily go through the insulation of a cable, poking a screwdriver in is less likely to (unless you hit it with a hammer of use a lot of force).

Use common sense, stop drilling when you break through on a cavity wall. If it's plaster dabbed on brick with a small cavity, stick a screwdriver in to feel for a cable when you hit the gap then continue drilling the brick.

coolbiking

Ah, makes perfect sense now Steve. Thanks for that.

slinky2000

just done the same this morning, poked through the plasterboard with a screwdriver, and hit the brick, I knew it was safe to continue drilling

coolbiking

Yeah, works a treat - still alive to prove it!

meercat

meercat wrote: »

these detectors are notoriously unreliable
as you have said the wiring should be vertical or horizontal(not guaranteed)
as its a stud wall the best bet is to drill slowly into the board and not let the bit go in too deep

a small screwdriver pushed gently into the plasterboard can do the job without the need for a drill if you are unsure,then just widen it to suit the rawl plug

Sorry to resurrect an old thread...

If you make the hole as the above, and there is actually a wire there, are you still safe enough putting the wall plug in given that it is plastic?

Would you also be safe enough doing that with nylon self drilling plasterboard fixings?

Thanks

TheShow

The plug will be fine as it won’t conduct electricity, the screw might though if you damage the casing on the wire when you screw in. Thread very carefully (no pun intended). Is it possible to move the wire slightly with the screwdriver?

2011

It is hard to advise without seeing it.
There are 2 main concerns:
1) Not to get a shock from the wire or to make the screw live.
2) To avoid damaging any wires within the wall.

Sleeper12

Deleted User wrote:

If you make the hole as the above, and there is actually a wire there, are you still safe enough putting the wall plug in given that it is plastic?

This has happened to me before. Unfortunately not every plumber or electrician runs pipes & cables vertical as they are supposed to be. I did make a screw live. It kept tripping the rcbo. The best solution at that stage was to bring in a Registered Electrical Contractor to make it safe. You can never be too careful