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  1. trf0412

    trf0412 Member

    Currently in the middle of a bathroom refit. Just had first-fix plumbing done and new flooring installed and plumber has sent me some photos of the pipework before flooring went down (see attached).

    The shower and sink waste combine into one before crossing the joists to get to the soil pipe. From the photo the plumber sent me, it looks like there must be a fall from the shower waste down to the sink waste (it's pieces of rigid pipework joined with a straight connector, so can't possibly be falling from both ends, right?). Also, I'm not sure why a T-piece that should be used vertically has been used horizontally? Anyway, my logical conclusion is that water will be permanently sat in the section of pipe between the T-piece and where it turns to go up to the sink. So, if I'm right, that leads to a few questions:
    • Is this going to pose a major problem or will the waste coming from the sink just displace the water in the pipe as it would be coming from a higher source?
    • Will this set-up result in the sink draining too slowly and backing up?
    • Is there a risk the sink waste could get into the shower tray (esp. with the strange T-piece that's been used, meaning the water will need to do a sharp left-turn)?
    • How about the water coming from the shower while showering? Will it all flow via the T-piece down to the soil pipe, or is there a chance it will push water back up the sink waste?

    WhatsApp Image 2017-09-01 at 08.48.27.jpeg

    WhatsApp Image 2017-09-01 at 08.48.16.jpeg
    • Funny Funny x 1
  2. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    Needs a fall on the basin pipe and that plumbing also isn't upto par

    • Like Like x 1
  3. trf0412

    trf0412 Member

    Can you give me more details about why it isn't up to par? I'm aware that plumber has drilled holes through joists higher than they should be, but would be interested to know what else you've spotted.
  4. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    Notching and holes arnt really correctly done

    Mix and match push fit fittings

    Inserts in plastic pipe ?

    Long left runs arnt clipped so possibility of a thud every time you close a tap if on mains pressure
    • Like Like x 1
  5. trf0412

    trf0412 Member

    By the way, my questions 1 and 4 had two parts, so I don't know which part your "yes" answers relate to. Depending on which part of the question you were replying to, the answers are complete opposites of each other...
  6. trf0412

    trf0412 Member

    Yes, the notching and holes are a bit of a mess... not really anything I can do about these now, apart from hope they don't cause an issue. The bits of reinforcing wood are only there because I insisted on having them, but I don't know exactly how much they will help things. (A lot of the notches are pre-existing ones, though, so not all done by our plumber).

    The mix-and-match fittings are probably due to the fact that we had a new boiler installed recently and the plumbers on that job used Hep20 pipe and fittings. Our current plumber uses Speedfit and has just continued on from the exisiting pipes/fittings, so I'm not too worried about this.

    Not sure what you mean by inserts in plastic pipe?

    Hmm... thud when turning off tap doesn't sound ideal... we have high pressure mains...
  7. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    First part will cause problems later on if it's falling the wrong way (blocking etc)
  8. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!


    That's fair enough thought he did the lot

    And plastic pipe require inserts internally to the pip

    Pic in attachment

  9. 1Steven

    1Steven Plumber GSR

    I never connect basin with shower.
    • Agree Agree x 3
  10. oz-plumber

    oz-plumber Plumber

    I've seen it all now.

    There is no way that the person who did the waste / drain pipe has any knowledge about plumbing.
    There is no way that will work correctly and will cause you insurmountable problems in the future.

    The way the junction is installed you cannot get fall from the shower or the basin.

    • Agree Agree x 1
  11. trf0412

    trf0412 Member

    Not something I can see, obviously, but I guess he used these. If they are a key element of the join, then presumably there would be leaks without them, right?
  12. trf0412

    trf0412 Member

    What makes you say we can't get a fall from the shower either? (I'm not saying you're wrong, I just have no plumbing experience/knowledge). Is it because half the water will travel down through the sink waste pipe and not all be diverted down the main waste? Would the water not fill up the pipe leading to the sink first and then, once it's full of water with nowhere to go, take the path of least resistence down to the soil pipe?
  13. Stigster

    Stigster Plumber

    Even six inches more waste pipe and an elbow would have improved that situation. Water flows downhill under gravity. Simple as that. Water will drain away from that system but it is going to block at the elbow from the basin because it's a low point/no fall. Soap, hair, oils will gather there.
    Last edited: Sep 1, 2017
  14. snowhead

    snowhead Well-Known Member

    That waste junction wants cutting out now and redoing.

    It would have cost 1 more 32mm Elbow and for the Tee to be in the correct orientation.
    Whoever did that doesn't understand how water flows and wouldn't have been aware of these either;

    POLYPIPE Solv 40 White Cross Tee .. WS38 | Priority Plumbing
    • Like Like x 1
  15. Best

    Best Trusted Plumber Top Contributor!!

    In short, - he isn't a plumber.
    Amazed that the "plumber" actually took those photos of that work he did and sent them to you!
    Bit like a burglar taking a selfie when stealing your property and then sending you the photo. :)
    Usually work like that is photographed by the customer to have proof or make complaint to the installer. (Or some of us take photos for hall of shame plumbing work)
    I wouldn't want the other work to be completed with same person.
    • Agree Agree x 3
    • Like Like x 1
  16. 1Steven

    1Steven Plumber GSR

    Now you have seen everything, fitted in a carehome. IMG_20170831_105753.jpg
  17. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    motorised up and down sink?
  18. 1Steven

    1Steven Plumber GSR

    No fitted in a sluice room. IMG_20170831_105745.jpg
    Waste is just held in with silicone. IMG_20170831_181116.jpg IMG_20170831_105745.jpg
  19. oz-plumber

    oz-plumber Plumber

    You have about as much understanding about how plumbing drainage works as your so called plumber.

    Fair enough, you probably don't need to know.

    But all the advice you have been given regarding the work done you had better take on board, because you will be accessing the drain in the near future if you don't have it corrected at this stage.

    Far cheaper to rectify now than after the bathroom has been completed.

    Just out of interest, you must have had some thoughts on whether it has been done correctly otherwise you wouldn't be asking the questions on here.
  20. bambers

    bambers New Member

  21. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

  22. Ric2013

    Ric2013 Plumber Top Contributor!!

    I would argue it is GOOD to have the tee horizontal. Less of a plug of water to cause induced siphonage if the tee is horizontal. But minimum fall should really be 18mm per metre and I agree you won't have anything near that. I know this under the floor, but I would like the design to be possible to unblock if it blocks, and you'll only be able to access via the traps, so poor design to have the tee there like that.

    The tee is designed to flow right to left and accept a branch from the bottom (ups and downs and lefts and rights based on your first picture being pinned to a wall) so it's in wrong. I don't like to see knuckle bends, unless strictly necessary (how will you rod that if it blocks?).

    I dislike sharing basin and shower wastes. I have done it, but would not ever do it out of choice.

    I have seen worse though, but personally would want it to be 100% correct if it won't be accessible again.

    Looks like your plumber has used copper pipe to transition from Hep to Speedfit which is the most correct way of making the transition.

    The purpose of inserts (according to a merchant who had spoken to a plastic pipe company rep) is they ensure the pipe is and remains perfectly round. They should always be used (unless you're making a joint that only needs to work for 5 minutes). Not sure how you can tell they are absent without dismantling.

    Hots and cold should not be run together unless properly insulated to keep the cold water at a hygienic temperature.

    If that were my house, I would want all hot runs lagged, but this would be above the industry standard, so you'd have to ask for this and pay extra.
  23. bambers

    bambers New Member

  24. trf0412

    trf0412 Member

    Sorry for the silence. For some reason I stopped receiving email updates, so didn't realise there had been more responses.

    Indeed. But my main concern was that the pipe travelling from the shower waste to the sink waste has a fall from the shower to the sink, and I was therefore concerned about the sink waste. But you're saying we can't get a fall from the shower either – that's the bit I don't understand, since there is a fall on that section of the waste pipe. But by the sounds of it I must be missing something. I'm not a plumber, so if I've misunderstood something please could you explain?

    Since I'm not a plumber, could you explain where you would put the extra 6 inches?

    What's the reason for not sharing them - i.e. what are the sorts of problems this could cause?

    This either means he's done something right, which is good, or the copper pipe was left there by the plumbers who replaced the boiler and rads.

    Yep, no way for me to tell if they've been used. I've a feeling I saw a bag of them, though, so I think he probably used them.

    I hadn't thought about this. But is heat-transfer such a big issue with plastic pipes? I guess it's less of an issue than with 2 copper pipes run side-by-side.
  25. trf0412

    trf0412 Member

    Thanks for everyone's responses. Good job I questioned whether the work so far is up to scratch as everyone is in agreement that this could (or should I say will?) give me problems. So, the next step is to ask how to tackle this?

    Obviously, when you've agreed for a tradesman to come in and do a job it puts you in a bit of an awkward position. If I call his work into question I doubt he'll be very happy and it will make me worried about him finishing the rest of the work if he feels I've undermined him. If I cut the work short, then there's the issue of how much I should pay him, and the added issue of finding someone else to finish the job off.

    And then there's a 3rd option – Would sorting out all the pipework from the floor below be feasible at all? There's already a section of the ceiling plasterboard missing below the bathroom (unrelated to this job) and we'll be having that re-plastered soon, so cutting out a bit section of ceiling to access the bathroom pipework won't be a problem.

    Any other ideas about how to handle the situation I'm in?
  26. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    Get him to re do it as your not happy better now than later
  27. trf0412

    trf0412 Member

    Hmm... I can try, but I know it'll be an awkward conversation. I already asked him whether he thought the lack of a fall would pose a problem and he basically said "it's fine how I've done it, just trust me please".
  28. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    well that would worrie me to the point of sacking him if hes happy with that hes defo no plumber
    • Agree Agree x 1
  29. trf0412

    trf0412 Member

    Right... sounds like I need to have a chat with him, even if it's an awkward one. Just so I am fully clued up before asking him to rectify things, could someone give me a list of what they would do to put this right? Would the following sort things?

    1) Cut out and replace the tee with an elbow (so shower waste is kept separate from basin waste initially)
    2) Take basin waste through 2 joists (although this would require drilling 2 more holes) before joining it back in with the shower waste (so that it has a fall on in before it meets the waste coming from shower)
    3) Clip pipes to joists

    Or would it be best to avoid step 2 by trying to get a fall on the basin waste before it joins up with the shower waste?
  30. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    hope this helps

    WhatsApp Image 2017-09-01 at 08.48.27.jpeg

    both can have independent falls and not tied by each others t in position

    you could ask him does he have an nvq in plumbing if he doesnt hes a handy man and not a plumber
    • Like Like x 3
  31. trf0412

    trf0412 Member

    Yes, that helps a lot - thanks!

    Such a simple, elegant solution and one which easily allows the fall on the basin waste to be independent of the fall on the shower waste. (Now I've seen the suggested fix, I'm amazed why he didn't simply do this in the first place?!). However, this will only work if the pipe going across the joists doesn't start so high up as to rule out getting enough fall from the basin... if it does, then I'm not sure what we'll do.

    So, in this set-up, would it be right to use the same tee that he already used (i.e. one that would direct the flow from the shower down to the right)?
  32. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    Makes me think he's not a plumber anyone can put pushfit pipe together And glue waste pipe

    Doing it correctly is another matter

    Should be more than enough might need to slot the joist the basin end but other than that should have a good fall on it

    No as you can't unglue the fittings
  33. trf0412

    trf0412 Member

    Hmm, maybe I should just take up floor and do it myself!

    Yes, I thought that might be necessary.

    Hehe! Sorry, I didn't mean reusing the exact same one, I just meant the same design.
  34. Chuck

    Chuck Active Member

    Tell your plumber that you have had your attention drawn to some defects that need rectifying. Make it clear that either he fixes it, and to a proper standard, or you will get another company who does understand what plumbing installed 'with reasonable skill and care' (use exactly those words) means.

    Your only decision, which largely depends on how much you value your own time, is whether to try and get the person who installed the mess in the photographs to fix it or cut your losses and get someone else to do it again right.

    I'm old enough to have learned you can't get blood out of a stone. In your circumstances I would write off any sunk costs to experience and get a reputable trader to redo the work to a more appropriate standard.
    • Like Like x 2
  35. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    Also you will need an anti vac trap on the basin

    I wouldn't do it my self either plumber does it or he doesn't get paid for the waste pipe simple and if he choose not to change the design of it by by get another plumber in
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