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Discuss Capping off a soil pipe in the Fittings & Pipes area at

  1. kc1

    kc1 New Member

    What's the best way to seal and cap this soil pipe before I concrete over it?


    Inside diameter seems to be just over 100mm. It's seems to be ceramic.


  2. Best

    Best Trusted Plumber Top Contributor!!

    It should be same internal size as new plastic soil pipes. You could use a standard 4" internal cap. It will have a ribbed rubber outer seal. Best get as heavy duty one as possible, but any will do.
  3. joni os

    joni os Plumber

    Ram a cement bag or similar 4" down the pipe as a stopper and then plug it with concrete.
  4. Best

    Best Trusted Plumber Top Contributor!!

  5. snowhead

    snowhead Well-Known Member

    How far away from a manhole is it?
    It should be plugged as close as possible to the junction to avoid a nice dry home for rats.
  6. kc1

    kc1 New Member

    Probably about 4-5m from the manhole. I'm assuming that other things in the house use the same feed into the manhole - but I would need to check to be sure. There is a WC close to the soil pipe in the photo, so I assume these connect together somewhere.
  7. joni os

    joni os Plumber

    Be aware, with old clay pipes joints are solid, sand/cement, and pipes are relatively fragile. Not unusual when breaking into pipe, for adjacent pipes to fracture. Unless there is space and inclination to excavate and relay broken pipes keep disturbance to minimum.
  8. Last Plumber

    Last Plumber Plumber GSR

    Cut a piece of slate to sit nicely in the collar and mix grit sand and cement 4:1, fill and level it
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