1. Visiting from the US? Why not try DIYnot.US instead? Click here to continue to DIYnot.US.
    Dismiss Notice

Re-locating bathroom - soil / waste advice

Discussion in 'Plumbing and Central Heating' started by rob7475, 27 Feb 2017.

  1. rob7475

    rob7475

    Joined:
    5 Jul 2006
    Messages:
    125
    Thanks Received:
    0
    Location:
    Leeds
    Country:
    United Kingdom
    Hi,

    I'm renovating an old one bed back to back. My plan is to turn the bathroom into a second bedroom and split the current bedroom to create a bathroom as the room is massive.

    The new bathroom will have no external walls so I've got a bit of a challenge with running the soil pipe to the front of the house. My plan is to run the 110mm between the joists to the front of the house before joining the stack. However, the joists are only about 8" so I'm going to struggle to get the 18mm drop on the pipe. As there will be a sink and bath discharging to the same pipe, would I be OK if the drop is a bit less than 18mm?

    My other option is to drop the pipe below the joists into the kitchen and box in - this would create upto 3 bends on the way out though - would that be worse than having a slightly lower drop?

    Another part of the plan is to run a vertical soil pipe in the store room next to the bathroom before the pipe disappears under the floor and fit an AAV due to the length of the run.

    Also, where would be best to connect the sink and bath waste into the soil pipe - I've attached a picture so you can get an idea of my plan.

    Thanks
     

    Attached Files:

  2. Absolute minimum fall is 18 mm/ 1m, recommended fall is 44 mm / 1m.

    Your run looks to be approximately 5 m so you need a fall of between 90 mm & 220mm. With a 200 mm joist depth and a pipe diameter of 125 mm (allowing for fittings), you only have 75 mm to play with.

    Not recommended!
     
  3. Sponsored Links
  4. Lower

    Lower

    Joined:
    22 Dec 2005
    Messages:
    2,131
    Thanks Received:
    293
    Location:
    UK
    Country:
    United Kingdom
    How high are the ceilings downstairs? Any chance of lowering them by a couple of inches?
     
  5. rob7475

    rob7475

    Joined:
    5 Jul 2006
    Messages:
    125
    Thanks Received:
    0
    Location:
    Leeds
    Country:
    United Kingdom
    Cant drop the ceiling as the window and door frame are almost at ceiling height.

    If i take the pipe into the kitchen, i can go below ceiling level and box it in to get the required drop. This would mean creating a couple of bends in the pipe though - is this ok with toilet waste?
     
  6. Sponsored Links
  7. Hugh Jaleak

    Hugh Jaleak

    Joined:
    3 Feb 2008
    Messages:
    7,334
    Thanks Received:
    1,720
    Location:
    Northamptonshire
    Country:
    United Kingdom
    Bends are frowned upon in the vertical sections, but if in the 'horizontal' run, are less of an issue. Just make sure rodding access is provided, (preferably outside for obvious reasons!), and ensure there is adequate fall on the pipe and you should be ok.

    Wastes, either connect with bosses as required, or look at a manifold at/below floor level.
     
  8. DIYnot Local

    DIYnot Local

    Joined:
    3 Sep 2019
    Country:
    United Kingdom

    If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

    Select the supplier or trade you require, enter your location to begin your search.


    Are you a trade or supplier? You can create your listing free at DIYnot Local

     
Loading...

Share This Page