UK Nicked wires from screws

[AlexBuz]

Hi everyone,

I've drilled a couple of screws through the floorboard as it was squeaking and driving me crazy and realised I might have done something really stupid. I've drilled quite a few screws through it and I realised the next day that I should perhaps used a stud finder to check for wires within the floor. The wires were 60mm long and drilled them through the floor into the studs.

My question is, how would I know or could check if I damaged any electrical wires when I've done this? No fuses were blown and nothing obvious happened. I'm now really worried I might have made a big mistake and no idea how I could check this.

I would appreciate very much any advice on this as I'm really stressing out now that it could cause a fire or some huge bill at some point.

 

[James]

2 ways I can think of.

1. lift all the floors you have screwed down and check what is below. (Note.. be sure to check the water stopcock turns off correctly before taking any screws out)

2. get an electrician to do an insulation test on the wiring to check if any cables have been damaged.

 

[buzzlightyear]

get an electrician to do an insulation test on the wiring to check if any cables have been damaged

and a plumber on stand by ,there's nothing like leaky house ,quick get the umbrella .

 

[James]

and a plumber on stand by ,there's nothing like leaky house ,quick get the umbrella .

Unfortunately a screw straight into a plastic or copper pipe will often self seal itself quite well and not start to drip for a few days when heat and vibration make it a slightly looser fit.

it will of course become a fountain the moment you remove the screw.

 

[buzzlightyear]

it will of course become a fountain the moment you remove the screw

bucket ready .

 

[Pretty Mouth]

Unfortunately a screw straight into a plastic or copper pipe will often self seal itself quite well and not start to drip for a few days when heat and vibration make it a slightly looser fit.

it will of course become a fountain the moment you remove the screw.

Had exactly this on a job last year. It hadn't leaked a drop for 8 months until I removed it, when a little jet of water shot out of the floorboard. Handyman had done it while fixing creaky floorboards.

 

[AlexBuz]

Hi everyone,

I've drilled a couple of screws through the floorboard as it was squeaking and driving me crazy and realised I might have done something really stupid. I've drilled quite a few screws through it and I realised the next day that I should perhaps used a stud finder to check for wires within the floor. The wires were 60mm long and drilled them through the floor into the studs.

My question is, how would I know or could check if I damaged any electrical wires when I've done this? No fuses were blown and nothing obvious happened. I'm now really worried I might have made a big mistake and no idea how I could check this.

I would appreciate very much any advice on this as I'm really stressing out now that it could cause a fire or some huge bill at some point.

Would applying a voltage meter on the screws help to see if there is any electricity going through them and if it does then it would clearly indicate I've hit a wire?

 

[timhoward]

Would applying a voltage meter on the screws help to see if there is any electricity going through them and if it does then it would clearly indicate I've hit a wire?

Assuming it's twin and earth cable in a house. If a screw just nicked and is touching one outer wire, then there is a 50 50 chance it's the live wire and could be detected this way. It's very unlikely to have taken out just the middle earth conductor.
If a screw nicked two wires you already know if there were Live and Earth as a breaker wouldn't turn back on. If they were Neutral and Earth you would already know if you have a modern consumer unit as you would have occasional RCD / RCBO tripping. (feel free to post a picture of the consumer unit so we can advise further on this).

I honestly think you are worrying too much. Plenty of people do things to houses that are a lot more reckless on a daily basis without engaging brain and get away with it a lot of the time. It's far more likely everything is fine than some damage has been done.

 

[telectrix]

if the cables were installed since c.1975, they should be min. 2" below top of joist, so unless you've used 3" or longer screws , fat chance of hitting a cable. best solution is to lift board/s and have a look see.

 

[MJPD29]

Would applying a voltage meter on the screws help to see if there is any electricity going through them and if it does then it would clearly indicate I've hit a wire?

No that is a waste of time. Correct test would be insulation resistance test. Get a spark to check it for you

 

[littlespark]

We were always taught to run cables through the joist in the centre of where a floorboard edge is, and screw it down at the outer edges.

 

[AlexBuz]

if the cables were installed since c.1975, they should be min. 2" below top of joist, so unless you've used 3" or longer screws , fat chance of hitting a cable. best solution is to lift board/s and have a look see.

Thanks for the tip, I've lifted the boards and unfortunately it seems that I've hit some cables which were right under the floorboard and all bundled together.... The screws were 60mm so about 2.36 inch. Is that a regulation in the UK to have them at least 2" below the joist?

How much would this cost to fix any idea? I've just notified the landlord who will get an electrician to check it and I'm hoping it's not going to cost me an arm and a leg

 

[MJPD29]

It's impossible to estimate how much without seeing it, depending on where its hit it may either be rewired (best option) or as a last resort a joint could be made. How many did you hit?

 

[nicebutdim]

Did something subsequently happen that made you think about the possibility of having hit a cable?

 

[brianmoooore]

The screws were 60mm so about 2.36 inch. Is that a regulation in the UK to have them at least 2" below the joist?

There's no reg. as such. The 50mm refers to how far a cable has to be away from the surface a cable has to be for it to be acceptable for it not to be protected by an RCD.
The holes for cables should be drilled in the 'neutral axis' of a joist, which in practice, means the middle, but this is a structural building regulation, not an electrical one. If the house has been rewired, an electrician is going to use existing holes if they are anywhere near the right place and size. It would be bad practice, from a structural point of view, to drill a new hole in the neutral axis if it comes close to overlapping an existing one in the horizontal plane, nearby.