Finding Partition Walls

[fido]

I was doing wiring work in a kit bungalow today, running cables in the loft and dropping them down through hollow partition walls. The problem was that there was nothing to indicate the tops of the partitian walls, just big expanses of plasterboard with joists in between. It was OK in places where there were already holes for light switch wiring as I knew I could safely drill near the existing holes. One cable had to go about 1.5 metres from such a bunch of switch cables and I managed to miss the partition by about 10mm, thus damaging the ceiling and wall plaster below. In the absence of any other datum I had measured an equal distance from the nearest roof support for the existing hole and the new hole.
What is the correct way of locating these walls? Should I buy some sort of electronic detector?
________________
moderator

more of a building question than electrical, so i have moved it

 

[andy]

I was doing wiring work in a kit bungalow today, running cables in the loft and dropping them down through hollow partition walls. The problem was that there was nothing to indicate the tops of the partitian walls, just big expanses of plasterboard with joists in between. It was OK in places where there were already holes for light switch wiring as I knew I could safely drill near the existing holes. One cable had to go about 1.5 metres from such a bunch of switch cables and I managed to miss the partition by about 10mm, thus damaging the ceiling and wall plaster below. In the absence of any other datum I had measured an equal distance from the nearest roof support for the existing hole and the new hole.
What is the correct way of locating these walls? Should I buy some sort of electronic detector?

usually, there is a beam for the wall at the top of the ceiling, so you usually have to take part of the plasterboard off at the top, so you then push something thru so you cna see it. long drill bits are good for this. once you get the cables down, then drop it down the gap, altho you sometimes have to work around the wooden framework

 

[legs-akimbo]

Get yourself some of them there X-Ray Spex....Great for looking at lady bumbs too!

 

[fido]

more of a building question than electrical, so i have moved it

I don't agree, a builder does not generally have to insert stuff into an existing studding wall. I would guess only electricians and plumbers tend to face this particular difficulty. At one time you could take up a couple of floorboards to run extra wires around a house but this is rarely an option these days, with laminate flooring etc.
______________________
moderator

edited to correct quote

 

[masona]

I use a long thin wood drill bit and drill a pilot hole at 45 degree from the inside just under the coving edge or the top corner of the wall & ceiling into the wallplate then backfill the pilot hole with a fine filler which shouldn't be noticable. Also make sure it's safe to do so. Another way is by tapping noise by hearing difference sounds. Will need a longer drill bit from the top if you hit a noggins.

 

[fido]

Thanks masona

 

[has]

Use a long thin terminal screwdriver right on edge of wall, hardly any hole to fill then.