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  1. erj

    erj GSR

    Hi I have a builder who needs to know how much water some flats he is building will use,

    they will have bath with a shower above, whb, wc kitchen sink , dish washer and washer, I have never been asked this be for in all my years . How do you work it out? thanks guys
  2. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

  3. Sparkgap

    Sparkgap Active Member

    If you're looking at flow rate per flat BS806 calculations give 0.42 l/s. This includes hot water usage.
  4. Chuck

    Chuck Active Member

    Don't. It's a trap. Tell the builder to ask the architect and/or engineers who designed the building to provide the figures they need.

    If you provide the builder with a figure you've got from an internet forum or a rule of thumb that turns out to be wrong you may end up liable for the remedial work, which for a block of flats could bankrupt you.
    • Agree Agree x 1
  5. jtsplumbing

    jtsplumbing Plumber GSR

    Absolutely agree all this should be provided on the design plans size of water main pipe runs location of water tanks etc. Have you seen the drawings for the site ? Have you got a copy ? Do you use a Scale rule to read the drawings ? All this information should be given to you if you are quoting for the work.
  6. Sparkgap

    Sparkgap Active Member

    I wish! A lot of the jobs we quote for come in half designed if at all and it's up to the contractor to size pipework, work out heat losses etc.
    BS806 is a nationally accepted standard so if you can show you've sized the system to it there should be no problem.
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