Earth Bonding your house

[tecnick]

I have recently changed the mains water pipe under the garden from lead to plastic. I ran the plastic along side the lead and connected at both ends leaving the lead insitue. I now have about 10-15m of lead pipe under the house desperate to be weighed in for beer tokens.
Can anyone tell me what to do about re-earthing the house if I now have plastic pipes.? Would the removal of the lead create more problems than it is worth in scrap?

Cheers Nick

[Jabba]

Pretty sure you can just put an earth spike into the ground near the house and use that for the earth bonding. Might be worth checking with an electrician though.

[varleym]

Nick

The primary earth will be via the consumer unit/fuse box and back to the incoming tails where they enter the meter. As Dave says, secondary earths can be provided to ground via a suitable earthing rod also cabled back to the consumer unit.

The only reason that metal (lead, copper, etc) pipes are bonded back to earth is in case they (and the fittings they are connected to such as taps, etc)become live under a fault condition. If you have plastic pipe feeding say a bath then there's no chance that the metal of the bath can become live, at least not via the pipes anyway.

Cheers

Mark

[Jabba]

I know that when United Utilities changed the power feed to my house in the Peaks from overhead cables to underground wires, they left me without any earth until I pointed it out to them! Only then did they connect the shielding /earth on the feed to my consumer unit.

[repton]

Can anyone tell me what to do about re-earthing the house if I now have plastic pipes.? Would the removal of the lead create more problems than it is worth in scrap?

It is almost certainly still earthed through the supply to your house. Check where the meter is and there should be an earth wire from your consumer unit into the box where the main supply company fuse is.

The link from there to your water pipes is simply to ensure that a faulty appliance doesn't leave all your taps and radiators live.

Paul

[tecnick]

Thanks chaps, the mains cable in does indeed split into live, neural and earth and the earth does indeed go into the consumer unit. The earth then re-emerges from said consumer unit and goes under the floor to bond onto the lead. So I assume then that bonding like this is belt an braces but worth sorting out just in case. What sort of length of spike is needed and do you just bang it in any where?

Thanks again Nick

[jim]

I would retain the lead pipe and bond it to the main earth terminal. The lead pipe in the ground provides extra security if you experience a fault on the incoming service cable.

[repton]

So I assume then that bonding like this is belt an braces but worth sorting out just in case.

It's partly belt and braces but mostly to make sure that a faulty water heater or shower or whatever can't make the pipes go live. With the pipes bonded to earth any such fault will result in a fuse/mcb blowing pretty sharpish thereby preventing the pipes going live.

This is something to be very careful of if you replace part of the pipework in your house with plastic, you have to be sure to have enough earth links to copper pipes that all the sections of copper are earthed. It is quite easy to end up with big sections of copper that aren't earthed in a mixed installation.

Paul

[Bo]

I've done this twice now, earth spike kits are available from Screwfix. In my old terrace house I fitted one in the cellar and connected it back to the earth in the board. In this one I knocked it in under the floor and earthed the indeed side of the stopcock. It's not really needed but better safe than sorry.

[tecnick]

Thanks guys for all advice. For the moment it will stay put as suggested by Jim. We hope to have an extension in spring so bathroom and kitchen will be new as will earth bonding. I will look at it again whilst there are some trades men (and women) around. Just hope they dont pinch the lead before I get it!!!

Cheers Nick

[Rod]

Leave it in or put in an earth spike, depending on soil conditions you can not always get a good earth reading with a spike been there done that I can remember 1 job where we had to fit 3 to get a reading, as long as you get a good Ze reading with what ever you go with it will be fine (this is a technical term that we electricians us to get your money)
A final point has your distribution board got any RCD's or RCBO fitted.
Bearing in mind when you have your extention built the electrian will have to put new or extend your existing circuits for the new rooms, so he should upgrade the distribution board to the 17th edition regs which means all circuits should have an RCD or RCBO on the end of problem.

Cheers
Rod

[tecnick]

main CU full of switches which look a lot like RCB's, as you say though Rod, let the sparkies sort it during extension work I just thought weighing lead in would help buy a few much needed bits for motor!!

Cheers chaps Nick