Connecting underground water pipe

8 Jun 2010
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United Kingdom
i have a 15mm copper supply to my house.

I need to run it into the house in a different location and cannot run a whole new main for various reasons.

I was going to access the pipe outside and then connect a 15mm full bore coupling to 15mm plastic and run around the house to the new location and then in.

I assume there we be no benifit in connecting to 22 or 32mm pipe as the restriction is already in the 15mm pipe?

Do I require a special underground coupling or will a standard John guest type be sufficient?

I will run the pipe in underground insulation.


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15mm copper? Really?

OK if so, I'd continue in standard underground blue poly, 20 or preferably 25mm (not much difference in price). Transition couplers are available - Philmac make good ones.

Speedfit is not recommended for underground services.
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Probably Table Y soft copper - only good stuff used in Sussex;)

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