Equipotential bonding and plastic pipes

[spooky_b329]

The water pipes in my house are copper, but I'm fitting a new bathroom soon which will involve cutting the copper about 6 - 12 inches from where it rising from the concrete floor, and then using polypipe and flexible braided pipe to connect to the taps.

Do I need to make provision for bonding between the pipe stumps rising from the floor to the light fitting? Behind the sink the metal pipes are likely to be reachable at floor level though the taps will be isolated by the polypipe.

Thanks.

(I know the WIKI mentions polypipe and bonding but not sure if this only applies when there is no copper in the room at all)

 

[robrudling]

The water pipes in my house are copper, but I'm fitting a new bathroom soon which will involve cutting the copper about 6 - 12 inches from where it rising from the concrete floor, and then using polypipe and flexible braided pipe to connect to the taps.

Do I need to make provision for bonding between the pipe stumps rising from the floor to the light fitting? Behind the sink the metal pipes are likely to be reachable at floor level though the taps will be isolated by the polypipe.

Thanks.

(I know the WIKI mentions polypipe and bonding but not sure if this only applies when there is no copper in the room at all)

OK - Equipotential bonding requirements as follows - 16mm main earth should be installed to all incoming services where they enter the house, Gas, Water etc... from the main earth bar. Then all copper pipes just need cross bonding near taps and gas appliances. therefore, all you should do is fix a bonding clamp to each of the stubs and a 6mm earth cable between them, nothing needed up to the light. The only time you would take an earth from an appliance would be to something like a metal window or other stand alone item in the equipotential zone.

 

[spooky_b329]

Hmmm...maybe I'm missing something here.

If my bathroom was all copper pipe, surely I'd need to have the pipework connected to the light fitting to prevent possible shocks between the fitting and taps. This is in addition to the earths from earth bar to rising main and gas pipes. As I understand it, the only exception to this is if all circuits in the bathroom are RCD protected.

Once I get this straight we can move back to my copper and polypipe example.

Thanks

 

[robrudling]

Hmmm...maybe I'm missing something here.

If my bathroom was all copper pipe, surely I'd need to have the pipework connected to the light fitting to prevent possible shocks between the fitting and taps. This is in addition to the earths from earth bar to rising main and gas pipes. As I understand it, the only exception to this is if all circuits in the bathroom are RCD protected.

Once I get this straight we can move back to my copper and polypipe example.

Thanks

As long as the copper pipes are continuous, i.e. back to the incoming main ( it should be) they are earthed this route, hence the 16mm back to the main earth bar.

 

[spooky_b329]

So as far as you're concerned I can ignore all this?

//www.diynot.com/wiki/electric...l_bonding:supplementary_equipotential_bonding

 

[JohnD]

16mm main earth should be installed to all incoming services where they enter the house, Gas, Water etc... from the main earth bar.

Wrong - 10mm

Then all copper pipes just need cross bonding near taps and gas appliances.

Wrong

all you should do is fix a bonding clamp to each of the stubs and a 6mm earth cable between them, nothing needed up to the light.

Wrong. 4mm to all the metallic services and to all the electrical circuit that enter the bathroom

The only time you would take an earth from an appliance would be to something like a metal window or other stand alone item in the equipotential zone.

Absolutely wrong

So as far as you're concerned I can ignore all this?

//www.diynot.com/wiki/electric...g:supplementary_equipotential_bonding[/QUOTE]
I think you would do better to ignore robrudling

 

[spooky_b329]

Thanks John and Rob.

Had to admit I thought it was a bit too good to be true, and flew in the face of everything else I'd read!

So John...from this:

4mm to all the metallic services and to all the electrical circuit that enter the bathroom

...I'm imaging that as my copper pipe enters the room it needs to be bonded even though it won't be connected to the taps?

 

[Spark123]

It depends on a few factors. Is the copper pipework accessable to someone using the bathroom? Is there enough plastic pipework to provide isolation between the copper pipe and the taps - what sort of length of plastic are you talking of?

 

[JohnD]

IMO if you have copper stubs coming up through the floor, its best to bond them. I expect you have radiator pipes too. You can bond the pipes just outside the bathroom wall, for example in an adjacent airing cupboard. Remember the immersion heater (if any), shower pump, central heating pump, electric towel eail, shaver socket etc. as well as the lighting circuit. Doing it in an airing cupboard is quite a neat way.

you only have to bond to the earth wire of each circuit once, even if that circuit supplies multiple fittings

some bathrooms have iron soil pipes and metal waste pipes which also need to be bonded

 

[spooky_b329]

Thanks everyone...polypipe sections will be quite short and under the sink the copper will still be reachable so will just bond the lot.