Stud finder. AC wire question.

Benzanna

Hi,
I've recently bought a stud find to use in my new build house.

It's working well, but there's one thing I'm unsure of.

I want to drill a couple of small holes to put up a bike holder (called a Clug - it's very small)

The stud finder says the entire wall has ac wires behind it - but only at certain points does the beep go off and the full bars show. Everywhere else it just shows the AC icon but not full bars.

Does anyone know if anywhere may be safe to drill? If not, I'll be attaching a batten with grip it style glue and drilling to that.

Help really appreciated.
Thanks

Grenage

I normally just avoid cable safe zones (you can look that up as a quick reference).

Trapdoor

If it’s a new build, then code says that cables must conform to certain routes within walls.

As a general guide, cables (which should have capping if under plasterboard dot &dab) should run vertically from the socket or horizontally from a socket. They shouldn’t Zigzag all over the wall.

So check where you are fitting the item. If there is a socket or switch or lamp or whatever vertically above or below, don’t fit it there. But if there is nothing in the vicinity you SHOULD be safe. But use the stud finder to verify. It should beep a warning, the AC icon may show it is a bit too sensitive but when you are over a cable it should show full bars. Try it near a known socket first.

Benzanna

Trapdoor wrote: »

If it’s a new build, then code says that cables must conform to certain routes within walls.

As a general guide, cables (which should have capping if under plasterboard dot &dab) should run vertically from the socket or horizontally from a socket. They shouldn’t Zigzag all over the wall.

So check where you are fitting the item. If there is a socket or switch or lamp or whatever vertically above or below, don’t fit it there. But if there is nothing in the vicinity you SHOULD be safe. But use the stud finder to verify. It should beep a warning, the AC icon may show it is a bit too sensitive but when you are over a cable it should show full bars. Try it near a known socket first.

Thanks
There are no sockets nearby at all. The wall backs onto the downstairs loo (no sockets there either) so I have no idea what the wire is for that's showing full bars...
Thanks for your help.

Undervalued

Is the plasterboard foil backed for insulation purposes? It often is these days and that can give false readings.

If your detector is adjustable try it somewhere you know there is a cable and turn the sensitivity down until it only just responds when in contact with the wall above the cable. Then try it where you want to drill. If no response then gradually turn it up until it does respond. If it is then the same all over the wall then I would suspect foil backing.

Another option is to drill only 3/4 of the way through the plasterboard (put some tape round the drill to tell you when to stop. Then cautiously "drill" the last bit with a screwdriver and took through the hole with a torch.

Norman_Castle

As above, I would suspect either the reading is wrong or you are not using it properly. Bodge a hole with a screwdriver. If it feels like anything other than plasterboard stop and look into the hole to see what's there. If there are wires in a cavity they will be hanging loose and move if touched making them unlikely to be damaged.

DaftyDuck

Go and try it where you know there are live cables, practice. Work out how sensitive and accurate it is there.

Try the wall with power off at the mains...