foul drain

  1. S

    New WC - Does it need a stack/SVP/AAV or can it go direct out to manhole?

    Please help, urgent! First post here, hoping someone can advise. We're planning a new WC in a garage, attached simplified sketch shows the plan. A builder we've been talking to has suggested a 110mm connection leading directly from the WC through the slab, then changing direction slightly to...
  2. C

    Foul waste and open gully

    Can the foul waste from a WC go on the same underground drain as an open gully? Basically the the gully would drain directly into the foul waste pipe? Hope the sketch below shows what I mean. Black is existing, blue is new. I can't send the WC drains to the SVP because there isnt enough fall...