Earth bonding with metal pushfit

[AdamW]

I am installing a new bathroom next week (whether I get it finished or not is a different matter!).

Now, I am using copper pipes and am considering using copper pushfit fittings. Do these provide sufficient earth continuity or would I need to cross bond the pipes going in at either end?

Is it sufficient to earth a complete 4 metre run of copper pipe only once along its length? At one end is a solid metal (and rather conductive) shower mixer, at the other end is a plastic flexible pipe to connect to a twin impellor pump. Only 1m of pipework is accessible, the rest is buried in the wall or behind the bath (not just the bath panel!).

 

[sterose]

I am installing a new bathroom next week (whether I get it finished or not is a different matter!).

Now, I am using copper pipes and am considering using copper pushfit fittings. Do these provide sufficient earth continuity or would I need to cross bond the pipes going in at either end?

Is it sufficient to earth a complete 4 metre run of copper pipe only once along its length? At one end is a solid metal (and rather conductive) shower mixer, at the other end is a plastic flexible pipe to connect to a twin impellor pump. Only 1m of pipework is accessible, the rest is buried in the wall or behind the bath (not just the bath panel!).

To the best of my knowledge, the pipes would have to be earthed, but I doubt there is any need to 'jump lead' the pipes at every single fitting.

As an aside, I have to wonder why you are using copper pushfit? Besides the scare stories of push-fittings bursting apart, they are expensive, you say they will be hidden, and they are no better really than compression.

Anyway, I suggest you simply earth the pipes as close to the taps as possible, and near the impellor pump too. And don't forget the radiator too.

 

[AdamW]

I was only planning to use them for joints where I won't be able to access it after I tile the walls.

I put a lot of effort and thought into my DIY but I realise that at the end of the day, it is still DIY. So pushfit seems like a good way to guard against a situation where I don't do my normal sterling job at tightening up the compression joints.

 

[Big_Spark]

Push fit firring will not provide an adequate or acceptable earth path, the seal is made by a rubber ring so ther is no or very little at best, metal to metal connection.

This is a problem we, as a company, have encountered on an increasingly regular basis. Experimentation has shown that the Earth path becomes truncated at best, completely disconnected at worst, notmally the path is simply not there.

It may look ugly, but to comply with BS7671 these push fit joints MUST be cross bonded, to confirm this, before posting, I asked the NICEIC technical help line, and they concur this is the situation.

 

[AdamW]

I had a suspicion that this would be the case as I figured there would be something rubber gripping the pipe.

OK, out with the spanners it is then.

FWL, would you be happy (in theory) with the earthing of an installation where the nearest earth tag was 3-4m up-pipe of the shower mixer, using only compression fittings and thus maintaining the earth continuity?

 

[sterose]

With said revelations, I would suggest you earth all visible parts, all pipe near teminals (i.e. taps), and that you attach an earth strap to the mains pipe (ie. before the pushfit fittings) and then run the earth lead back to the CU.

For pipe than isnt visible, forget about it. Just make sure it's not accessible.

 

[journeyman]

Why not just use plastic push fit plumbing in the bathroom. Make it into an earth free zone. The safest method of all. Plastic plumbing does not leak if it is correctly fitted.

 

[ban-all-sheds]

Umm - what's wrong with soldered joints?

 

[AdamW]

Well, that could be a good idea I suppose.

OK, lets change the question a bit then:

I am refitting my bathroom. There will be nothing electrical within Zone 3, the nearest electrical device will be the electric towel radiator a good 80cm from the bath. The shower mixer bar is a big heavy lump of metal and should (nay must) be connected with copper pipes via a couple of tap wall-plate elbows (which are metal).

If I use plastic piping and connectors up to the last stretch of copper piping (which will be concealed in the wall) do I need to earth the shower mixer bar (which is metal and funnily enough will be touched with wet hands) to comply with regs?

I know there is a 0% +/- 0.0000001% chance of ever getting an electric shock off a non-earthed mixer that is connected a good 1.5m from the nearest electrical wiring but I would feel a right wally if I got a jolt in the shower.

 

[ban-all-sheds]

this might help

but probably won't. It does make one interesting point, though

However, in most types of building, conductive parts such as non-electrical services or exposed structural metalwork are generally accessible to be touched by persons who may be in contact with exposed-conductive-parts (including those of portable equipment) or extraneous-conductive-parts. Even where this is not initially the case, consideration should be given to the possibility that it may become true later during the life of the building, due to changes in the mechanical and/or electrical services installations or in the use of the premises.

BTW - 80cm from the bath is in Zone 3. Zone 3 extends to 3m


WOW - post #1000.....

 

[AdamW]

BTW - 80cm from the bath is in Zone 3. Zone 3 extends to 3m


WOW - post #1000.....

Yes, I realise now re-reading it that what I said reads incorrectly. Zone 3 starts at 60cm from the bath, I meant to say "nothing electrical nearer to the bath than Zone 3"

Congrats on the millenium score!

 

[ban-all-sheds]

I can comfortably span 1.5m from 1 hand to another i.e. without stretching, and able to grasp things with each hand...

 

[Big_Spark]

I can comfortably span 1.5m from 1 hand to another i.e. without stretching, and able to grasp things with each hand...

You bragging again fella

 

[AdamW]

A fact that is hard to believe until you check it, a man's armspan fingertip to fingertip is usually pretty much exactly his height...

I can imagine a hundred people all reaching for their 6-foot spirit levels now!

 

[securespark]

Hate to brag, everyone, but my span tip to tip is 6' 8", and my height is 6' 1".