1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Discuss Grohe Sink Trap doesn’t fit pipe in the Plumbing Forum area at UKPlumbersForums.co.uk.

  1. Profic

    Profic New Member

    Hi All,
    We recently purchased a Grohe sink and sink trap. However the Grohe pipe is smaller than the standard fitting. Have tried local plumbers merchants and supplier to get an adaptor but no one seems to be able to supply one.
    looking for a 32mm - 34mm adaptor.
    Any suggestions?



  2. Craig Watson

    Craig Watson Plumber GSR

    You need a 1 1/4" compression fitting
    • Agree Agree x 1
  3. snowhead

    snowhead Plumber

  4. Profic

    Profic New Member

    The Grohe bit is 32mm but the wall fitting is 34mm. Ideally looking for a 32mm - 34mm adaptor? Or plastic ends with the different sizes?
  5. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    11/4 compression elbow
    • Agree Agree x 2
  6. rpm

    rpm Trusted Plumber Top Contributor!!

    Certainly wouldn`t reuse what`s in the photo regardless of whether it fitted or not!
    • Like Like x 3
    • Agree Agree x 2
  7. Riley

    Riley S. Mod Trusted Plumber GSR Top Contributor!!

    Def 1.25” compression
  8. oz-plumber

    oz-plumber Plumber

    That fitting under the plastic elbow in the picture, is the fitting I think you use to connect the horizontal pipe from the trap, to the pipe coming out of the wall.

    You will either need a pipe socket to 40mm or 32mm thread. (depending on the thread size of the fitting )

    That's how we do them.
    Some people just push the trap pipe inside the PVC pipe and silicon it.
    I wouldn't recommend this method
  9. Riley

    Riley S. Mod Trusted Plumber GSR Top Contributor!!

    Isn’t that fitting just a shroud for where it passes through the wall
  10. oz-plumber

    oz-plumber Plumber

    More explanation:
    The fitting in the bubble wrap is the shroud ( left side of pic )

    Fitting under ( right side of plastic elbow) is the fitting that seals the chrome pipe to a threaded fitting coming out of the wall
  11. Craig Watson

    Craig Watson Plumber GSR

    So that fitting next to the elbow threads onto a typical 1 1/4" compression fitting and acts as a push fit adaptor?
  12. Riley

    Riley S. Mod Trusted Plumber GSR Top Contributor!!

    Sorry oz yes, If I open my eyes I will see
Similar Threads - Grohe Sink Trap Forum Date
Grohe tap fitting 15mm flexi vs 21(?)mm valve thread Valves & Taps Jun 23, 2019
Grohe Rapido Smart Box Bathrooms, Showers and Wetrooms Jun 16, 2019