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Hello all,

I have just dug a trench to run an electricity supply from the house to an outbuilding (trench is 9m long and 500mm deep) and it occurred to me that I might as well run a (cold) water supply while I am at it (and while the path is dug up!).

Presumably MDPE pipe is correct for this application? Blue or black?

Is it OK to run MDPE water pipe and SWA armoured cable in the same trench? (I shall ask my electrician this one too).

As far as the water is concerned, is this as easy as dropping a length of pipe into the trench with appropriate fittings on the ends? An isolation valve at the source end of the pipe would seem sensible, but does it need a no-return valve as well?

Can the fittings (elbows etc) for MDPE pipe be burined directly, or do they need protection?

Thanks in advance.

CH
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cmhicks wrote:Hello all,

I have just dug a trench to run an electricity supply from the house to an outbuilding (trench is 9m long and 500mm deep) and it occurred to me that I might as well run a (cold) water supply while I am at it (and while the path is dug up!).

Presumably MDPE pipe is correct for this application? Blue or black?

Is it OK to run MDPE water pipe and SWA armoured cable in the same trench? (I shall ask my electrician this one too).

As far as the water is concerned, is this as easy as dropping a length of pipe into the trench with appropriate fittings on the ends? An isolation valve at the source end of the pipe would seem sensible, but does it need a no-return valve as well?

Can the fittings (elbows etc) for MDPE pipe be burined directly, or do they need protection?

Thanks in advance.

CH
==

Yes they can go in same trench but water needs to be a minimum of 750mm deep from ground level

Lay the MDPE on 50mm of sand and cover with 100mm of sand, no additional protection required

Yes i would install a non return valve

[quote="stokedan1"]Yes they can go in same trench but water needs to be a minimum of 750mm deep from ground level[/quote]
Hmm... more digging this weekend then! Why so deep? Frost protection? The SWA cable has no minimum depth, but should be "deep enough to avoid likely damage" according to my electrician.

[quote]Lay the MDPE on 50mm of sand and cover with 100mm of sand, no additional protection required[/quote]
Can MDPE compression fittings be safely buried, or is that asking for trouble in the future?

Thank you for your help.

CH
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