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  1. kakawak

    kakawak New Member

    hi guys,

    im looking to cut copper pipe underneath floorboards leading to the imperial radiator thats currently there. can someone advise on best solution to my problem?

    i cant bung the tank because whoever installed the water tank in the loft leaves me no access to get into it above. the only way i can see is using a selfie stick with a phone to view any issues from above :(

    i know your going to say just drain the system etc... but i also have another problem.. whoever installed the small radiator in the dinning room has the drain valve behind the skirting board :/ i have been told that these drain valves are temperamental meaning it might spring a leak or something and due to position its not something i want to really get bogged down with!

    so, is there a way to cut the pipe with the water still being in the system? im assuming that my pipe are imperial and was told to use an imperial to metric straight coupler 15mm. i will upload photos to show what i intend to do, hopefully my diagram will help :)

    you will see in the photo how my current waste was setup...notice the ubend being higher at one end!!!! lol it was terrible.

    what is the tolerance of a drop from bath to u bend under floorboards to stop a syphoning effect because if i opt to have my s bend above floor this is how it will look (see photo) or i can drop straight down beneath floor boards and have my ubend there :) please advise.

    i know im asking alot of questions for my first post so please forgive me!!!

    thanks for help in advance







  2. sammathias

    sammathias GSR

    i would either do it live as its only tank feed...wouldn't recommend tho. bung the tank outlet and vent, freeze pipework or drain down...(that drain off on the valve in the skirting boards are very reliable...)

    nothing wrong with that bath waste?
    • Like Like x 1
  3. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    Freeze the pipe
  4. kakawak

    kakawak New Member

    yea but would you opt for the ubend under floor with a drop from bath? im going to leave a hatch under bath for access my worry was regarding the drop!

    im definitely using the freeze option...any cheapish recommendations on brand and ease of use? what is the average time from frozen to thaw out when cutting pipe? if im only cutting 2 pipes how many cans will i need?

    if i hook up my sink to 32mm plastic pipe (pushfit) using a bend going down with it connecting to a 40mm pipe, what is the best way to do this? cant see any 32mm to 40mm pushfit reducer in a bend format. is the only way to use solvent weld attachments?

    can i reuse 15mm plastic pipe that was used in my old bathroom? if not, what do you recommend as i will be using plastic on copper pipe once i use the plastic pushfit metric to imperial coupler. do i need to wrap the plastic pipe in the wall once i chase it?

    Last edited: Jul 12, 2018
  5. sammathias

    sammathias GSR

    Well a deepseal trap would be better 75mm. Or you could just fit a hep20 waterless trap.

    I tend to just use artic spray freezer 500ml can will do two seperate 15mm pipes, plug should last 20-30 minutes but I never hang about. I would turn valves off and take off rad then do all your necessary pipework with valves on the ends leaving the final connection to your existing pipe before starting to freeze so it's a quick turnover. Doing one pipe at a time

    Not quite sure what you mean about the 32/40mm pipe? Only tend to use solvent weld. But you can cut a 32mm socket off a fitting and it will fit into the 40mm fitting acting like a reducer...

    Hate plastic pipe but for DIY I suppose it's acceptable. No harm in reusing pipe but I wouldn't reuse fittings too much...don't have to be protected in wall.
  6. snowhead

    snowhead Well-Known Member

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