Posting a message to the forum will remove the above advertisement
  1. Hi, welcome to the new look - Login with your usual login details, or sign up if you don't already have an account. If you post just once, all the advertisements get automatically removed. We have some competitions coming soon, and lots of new feaures. 

Discuss double check valve requirements for incoming mains. in the Water Regulations area at

  1. Tomsafe

    Tomsafe GSR

    Hi all,
    current job to replace old lead incoming mains for 25mm poly pipe, from the meter in front garden to kitchen at back of house, 3 bed semi with a combi boiler,
    !question! do I need to include a double check valve on the incoming mains water valve arrangement.
    many thanks
  2. dancinplumba

    dancinplumba Trusted Plumber GSR

    your meter will act as a non return valve, but you will require a small expansion vessel (150ml) to take up thermal expansion
  3. chris watkins

    chris watkins Plumber

    No Tom you don't need one,
    With all due respect if you are going to start messing around with water / water mains you really do need to do the Water Reg's course, then you be able to self cert & know what is & isn't required.
  4. Tomsafe

    Tomsafe GSR

    Yes true, it's a one off job I don't normally touch domestic, but didn't want to install incorrectly, think I'll pass this one off to a local plumber then.
    Thanks guys
Similar Threads - double check valve Forum Date
installing drinking water fountain, double check valve? Plumbing Forum Jul 9, 2017
Air in Hot and Cold Water Supply to Bathroom Double Sink Taps - Non-return check valve help? Bathrooms, Showers and Wetrooms Mar 31, 2017
Outside tap and double check valve Plumbing Forum Sep 15, 2016
Double check valves and high water pressure Plumbing Forum Sep 13, 2016
Outside tap internal double check valve Plumbing Forum Mar 20, 2016
Double posts and very slow forum Plumbers Arms Jan 15, 2017
armitage shanks kensington double trap siphoniic toilet Plumbing Forum Jan 5, 2017

Users found this page by searching for:

  1. incoming mains requirements

  • Users found this page by searching for:

    1. incoming mains requirements