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Discuss What size pipe to use for garden tap - long distance 80m? Overground not buried in the Fittings & Pipes area at

  1. Anakin

    Anakin New Member

    Two things. Customer has a huge garden, requiring a tap at the end. Firstly is it best to use say 25mm bore plastic pipe? Will I get better pressure by using a larger bore pipe, or lose pressure over that distance? Direct off mains.
    Secondly the customer does not want their garden dug up to put this pipe in a trench, and is mostly unseen next to a hedge. The blue pipe is meant to be buried to protect from UV, and it would cost a small fortune to lag that much pipe. Pipe will be shut off and drained in winter, so is there a particular overground exposed pipe I could use without lagging? Or is the sunlight damage thing just scare mongering and will be fine to use?
  2. kozak1968

    kozak1968 Plumber GSR

    They make black poly for above ground. As for diameter it would also depend on pressure and flow rate.
    • Agree Agree x 1
  3. Matchless.plumb

    Matchless.plumb Trusted Plumber GSR

    You would also have to dig up the trench about 750-1350mm so it's not as easy either. Apparently you do not need to lag the pipe in ground if you lay it between 750-1350 but me personally I would always do it. You could install it n a duct or lag it as you already have mentioned. But as above you can get black mdpe pipe
  4. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    whats the pipe going to be used for?
  5. Stanios

    Stanios Plumber GSR

    If I was the cust I'd just get standard garden hose 100m and attach it to existing tap.
    • Like Like x 1
  6. zzzjim

    zzzjim Well-Known Member

    Is the garden on a gradient ?
    ( or pretty flat)
    .. Do they have a pet that likes chewing hosepipe..
    • Like Like x 1
  7. chris watkins

    chris watkins Plumber

    Are you a Plumber Anakin?
    Do you hold your Water Regulation ticket ?
  8. Anakin

    Anakin New Member

    I am a plumber yes lol. I wouldn't normally involve myself in jobs involving pipes underground.
    At the moment they do use a really long hose pipe, but don't want to walk the distance to the first tap to turn it on and off, and clearly they can't have the mains fed all the time through the hose, i.e leave the first tap on if a new one put on the end..
    It's just a water supply for some veg gardens at the back. I just hope the double check valve, doesn't restrict the pressure too much, or jam up like they can do.
    Black mdpe pipe it is, I'll go for 25mm.
  9. Ric2013

    Ric2013 Plumber

    Just make sure that double check valve is at the source so the water, stagnant in the pipe, can't backfeed the mains when it warms up from sunlight. And they jam because they freeze - the double check valve should be indoors. How about a mini-expansion vessel to allow for expansion or is MDPE forgiving enough? Whether or not you're a plumber, let's just hope you do it right! I don't know what's right - I'd be asking the same questions as you...
  10. AWheating

    AWheating Trusted Plumber GSR

    imo only good solution is to put in ground.
    • Agree Agree x 1
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