live wire detector-needed?

[koolkat]

I have to put up a number of shelves and cabinets in my flat. It is a council property so I assume the wiring is done to regulation, so cables should run up or down from plugs etc. However, I still not feel very confident as there seem to be many plugs, pipes etc. I bought a stud/ wire locator from B&Q a while ago and didn't find it easy to use or helpful. Is there a better brand or a safest way to do this?
Thank you

 

[rjm2k]

They are all a bit hit and miss tbh, check the wiki for safe zones as it's not as simple as up or down.

There's a video on youtube of a guy using a detector, he recommends using a blunted nail when going into plasterboard, the idea being that if it's blunt it wont pierce anything too easily and you may be able to tell there's a cable/pipe in the way by the sound the nail makes or it bouncing back when gently hit.

Detector wise I have a Zircon, a B&D combined laser level, a rapidtest and a LIDL or ALDI multidetector which I would "rely" on in that order.

 

[koolkat]

Would wire/ pipes etc just be embedded behind the plaster rather then deep into the concrete?

 

[PrenticeBoyofDerry]

Unfortunately the reliability of the standard cable detectors are not that great and have yet to come across one that I would be willing risk my life on and drill confidently with power on.
And locating pipework for plumbing has become more of a headache with the increasing installation of plastic speed fit, HEP2O etc....
So I agree with rjm2k, that this safest method would be to create a small hole using an old screwdriver or blunt instrument and do some digging around.
This link will describe the permitted safe
//www.diynot.com/wiki/electrics:installation_techniques:walls
But do not accept that the installation conforms to this.

 

[PrenticeBoyofDerry]

Would wire/ pipes etc just be embedded behind the plaster rather then deep into the concrete?

It's unlikely that they would be embedded deeply, but deep enough to perform the method used to coat the wall with render/plaster/plasterboard and cover over the pipes/cables sufficiently.

There regulations concerning depths that chases can be in the wall.
These are 1/3rd of the wall's leaf/skin on the vertical and 1/6th on the horizontal. But again do not accept these regulations have been abided to.

Do you know the method and material construction of your walls.

 

[koolkat]

It is a council estate, not sure what year, it seems to have concrete walls with a heavy plaster coating. I tried drilling once and the drill bit with the hammer action wasn't going in after the plaster coating (although I did not push, just in case)

 

[PrenticeBoyofDerry]

So they are solid walls!
Then best method is to mark out the location of fixing, then with small blunt implement, do a little digging to expose the solid wall. If you have not come across pipe/cable should be safe to drill holes.
Suggest that you isolate the electric whilst digging, to prevent and potential electrical hazards.
Always use a decent masonry bit or it will be hard work.

 

[Scoby_Beasley]

It is a council estate, not sure what year, it seems to have concrete walls with a heavy plaster coating. I tried drilling once and the drill bit with the hammer action wasn't going in after the plaster coating (although I did not push, just in case)

After following Prentice boys excellent advice, go and beg, steal or borrow an sds+ drill from someone. Will go into those walls like a hot knife into butter!!

 

[dhutch]

In my mind hammerdrill=sds anything thats non sds is bearly worth bothering with.

So far (and im grabing onto all the timber I can) ive managed to avoid all wires and pipework using common sense and a fairly good knowlage of where my ring main and pipes are run, long may this be the case.

I have also used the 'blunt screwdriver test' to locate a wire I knew I wanted to drill very close to and ran against the brick behind dot and dab plasterboard and I would certainly recomend doing it with the power off, as plasterboard is harder than pvc making it very hard to notice what youe digging holes in. I managed to stop with only minor damage to the outside of the secondary inslulation, but more by luck than judgment.


Daniel

 

[Scoby_Beasley]

A bit off topic, but a cautionary tale.

My ex Ma-in-law wanted a curtain rail putting up in the kitchen. A typical 70's Woodrow council house (even called the estate Woodrow!). Now, for info, prior to her moving into this house it had been subjected to a house fire.
So. I gets me drill out, drill a hole in the plasterboard through to brick (?? laughable) for the end bracket etc. etc.. Second hole a foot into the window space. I hit the metal lintel. Damn thinks I, I get down and change the drill bit to HSS, light a tab and jump back up on chair. I lean on the drill like a maniac. PSsssHHHT!! It wasn't a steel lintel at all. It was a ferkin copper gas pipe above the window frame!! I tell ya, you've never seen anyone shift so quick to turn the gas off! (and I'll admit I was highly "shaken" afterwards).

At the end of the day, despite "deliberate damage" and an emergency call out, the LBC came out and said would be no recrimination towards the tenant as the gas pipe should not have been hidden up there (+ MIL was a pensioner!). If the contractors thought/knew the original gas pipe under the floor was damaged then they should have dug the floor up and replaced it there. That was part of their contract remit apparently.

Moral:- Never, ever, assume anything!!

 

[Iggifer]

I once watched a guy accidentally drill into a core of a 3P+N supply to a 250a submain (was fed in SY but inside the panel it was stripped back) so when he shorted between earth (panel) and L2 it made a VERY big bang. There wasn't a drill bit left and this guy must have let out a little bit of wee.