Underground mains water pipe size

[Eng33]

About to reroute / replace underground mains water supply pipe from water meter (near street) to stop cock, which is a run of approx 15m. All existing mains cold in the house (bungalow) from the stop cock is 15mm copper, so will 20mm MDPE be OK? Got an awkward bend to negotiate, so would prefer not to use 25mm....

Thanks.

 

[kevindgas]

think you will find that your water board will require 25mm and a sleeve if it passes through a wall. they may also expect you to put in a double check valve at house end.
would ring them to check if I was you.