Drilling into concrete ceiling

[blunt]

Hello

I live in a purpose built flat with solid concrete floors, walls and ceilings. I'm trying to replace the lights in our hallway. I think I'll be OK with replacing the current ceiling roses with the ones that come with the track lighting, but my problem is with drilling the ceiling for the track mounts.

I have bought two different wiring/pipe/stud detectors and according to both of them the entire ceiling is either live or made of metal. Is there any way I can find out where it's safe to drill?

Thanks
Rog

 

[rebuke]

I would guess if it's concrete the detectors are picking up rebar (http://en.wikipedia.org/wiki/Rebar) - the steel reinforcement that is often used.

Assuming the only thing that's chased in to the ceiling is the cable for the light fitting, I'd suggest you get something such as a volt stick, this should light up if it detects a voltage, so might allow you to trace the cable(s) to the ceiling rose. Note however that I haven't worked with concrete ceilings before, so what I'm suggesting might be complete rubbish...

 

[xerxes]

I'm not sure a volt stick will help, at least not reliably.

Mine (I have three different makes) light up only when held very close to a live cable; you can distinguish between the line and neutral on a flat twin and earth cable, because the light will show for one side and not for the other. On the other hand, my Bosch detector distinguishes between concealed metal and concealed live cables. However, I don't know if it would work through any depth of concrete.

My suggestion (and it comes with the same disclaimer as Rebuke's) is to work out from the external evidence (fittings, etc.) where the cable run(s) probably are, and drill to avoid it or them, using the shortest fixings consistent with the weight of the track lighting that you can.

Or you could glue the fitting onto the ceiling (!).

Why not try asking this in UK Electrics?

 

[noseall]

i think this might be an advert.

 

[blunt]

Hi

Thanks for the replies. It wasn't an advert, I just thought that it might help responders to see what I was trying to fit.

I did think about whether I should post in UK Electrics, but as my query had so little to do with the actual connecting to the electricity, I opted for general DIY.

Gluing is not really an option as the ceiling is textured, but perhaps if I open the ceiling rose I might be able to see how deeply the conduit is buried and work around that (hoping it stays constant)... and I might yet try the volt stick - I've seen some called "non contact".

Thanks again xerxes and rebuke for the responses.
Rog