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Discuss ADVICE-40mm waste leaking ceiling. Pipes at angle/undefeated pressure? in the DIY Plumbing Forum area at PlumbersForums.net

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Hi

I fitted a bath/shower 12 years ago and a few months ago it developed a leak.

It was basically at a coupler on 40mm solvent where my new white PVC joined the existing grey PVC.

I cut a hole in the ceiling and could also easily view it with the bath panel off but not access it from there.

I cut us hole between the joist centres and the leak was easily visible as the pipes were not aligned vertically. There was a fair amount of pressure needing applied to ‘push them up’ to get them aligned.
Imagine it as an as them joining like ‘V’ but obviously not that aggressive but both at and angle downwards and pressure is needed to push them up to align.
I can’t believe the existing single coupler lasted that long tbh!

I repaired it s 4/months ago but putting in a new short piece of pipe and a x2 couplers either end.

I also put some 120mm screws in on both the pipes to support them take the pressure totally off the now 2 couplers that are touching each other with piece 40mm pipe in middle.
So it a 2 coupler join but with stress/pipes supported.

It seems to leaking again and I’m not sure how to proceed as I can only presume a screw had dropped/fallen at an angle but I put I few in.

The pipes run with the joist so there’s no bogging so there’s a nice bit of play there.
I have no problem making the hole in ceiling longer if needed and getting it boarded/plastered.


Is there an inline flexi solvent I could put in place ?
I know it’s not ideal as it would hold a small amount of water but it would get rid if the misalignment/pressure on the couplers.

I’m surprised it has leaked tbh as it was well glued and all pipes fully into the couplers.
What I did do though is full the bath and run it about 10 mins after the repair! Could this have weakened the joint?

Another possibility is that I have just moved te problem/stress to another joint.
It comes out of a wall one end so is fixed and he’s to bath waste the other end with a T near there for a shower.

I was also thinking after googling that some ‘plumber’ had resolved this by just heating some 40mm and bending it. This taking the stress off the joins plus where there will be a bit of water holding it will be on the solid bend of the pipe and not on the joins.

I’ll try do a basic drawing later when I have chance.

Any advice ur appreciated.
 
Could be pushfit early stuff was the same size as solvent
 
Hi, Yes it is, same size as the existing white is is joining to 40mm (act 43mm) solvent.

The problem is that the pipes meet at at an angle as in pic, it was just one coupler, but when i repaired it i used two as in pic (with bit 40mm in middle obviously) plus i added some long 150/170mm screws to support or push up each pipe so the joint would not part. Red circles are screws. Right side grey goes into wall/not much movement. Left white pipe goes to bath but has T in between to shower.

It's the angle they meet at is the problem, you have to literally push the pipes up to keep couplings in place!

This site is virtually unusable with all the POP UP adverts!! It's taken my 10 minutes to just reply!!!
Is there anyway around this??

PIC as is now with 2 couplers and support screws-


Cheers
 
I may be mistaken though.
But when I added the two couplers instead of the leaking one I’m pretty sure it was just as tight going on as it was the newer white pipe I fitted when I did the bathrooom 12 years ago.
 
Could you use 2 elbows to act like a swivel joint ?
 
Ah I think you mean just move them horizontally and connect using elbow or even 45s???
There definitely space between the joists.
Am I thinking correct here?
Cheers
 
Yes horizontal elbows would be easier you could use some 45s but would require a bit if planning on the angles / dry fitting
 
Yes horizontal elbows would be easier you could use some 45s but would require a bit if planning on the angles / dry fitting
So just cut it back again.
X2 couplers again and x2 elbows and allow the slight dip where the pipes be.
The bends will take the angle out.

Great idea. Let’s just hope it’s leaking there and not moved to elsewhere!!

Also what option do I have if the existing grey is push fit which I’m 99.9% it’s not?
 
Yes or if you want 2x 45 and no couplings

Mcalpine compression elbow
 
Yes or if you want 2x 45 and no couplings

Mcalpine compression elbow
Yes or if you want 2x 45 and no couplings

Mcalpine compression elbow
But when I cut out what is there I surely would need new couplings as I’m removing the 2 I already fitted.
The nearer I can get the pipes by re extending them then surely the smaller the gap/spread will be between them.

I have a McAlpine flexi coupler here. Compression both ends. It’s marked 1 1/2”
It’s fits nice onto the 40 (43mm stamped) white pipe I have left from last repair.

I just don’t like the thought of compression there though. Even though they are at the bath and shower. I think as it will be dipping it will be permanently holding water.

I may get away with no couplings as long if I clean any excess glue etc.

So it would just be x2 elbows and tiny bit if straight to join them.

Just like before but with elbows not couplers.
 
Just seen these as well.
I know the 1 1/2 max alpine double ended flexi conpression I have fits the new white pipe as I tried it earlier.

What is the purpose of this?

The compression end is obvious but what is the other end ?
Make or female?

Why don’t they just make a striaght flexi that has solvent both ends?
It would be a great seller imo.


Also attached the an old 40mm flexi coupler.
 

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Sorry, but going right back to posts #1, #2 and #5, the thing I'm not clear about is whether solvent glue works properly with your grey pipe? You major on the size being correct, but are you sure the solvent actually dissolves the surface of the pipe significantly, as it needs to do for a sound joint?
 
Sorry, but going right back to posts #1, #2 and #5, the thing I'm not clear about is whether solvent glue works properly with your grey pipe? You major on the size being correct, but are you sure the solvent actually dissolves the surface of the pipe significantly, as it needs to do for a sound joint?
Sorry, but going right back to posts #1, #2 and #5, the thing I'm not clear about is whether solvent glue works properly with your grey pipe? You major on the size being correct, but are you sure the solvent actually dissolves the surface of the pipe significantly, as it needs to do for a sound joint?

Good point but surely even if it was push it/compression it would be PVC?

I definitely remember when i first had the leak it was from the white pipe to the white coupler.
I’m certain if that as i pulsed it out and the coupler was still on the grey.

I’ll see if I can follow it back and spot any other fittings but u doubt it.

I’ve only seen videos of people using different glues on differing pipes but in the USA.

It looks/cuts like PVC.

What else do they use in the U.K. for waste?

I’ve seen the blue MDPE stuff for supplies and 4” soil stuff. that’s it tbh.

Stilll not had chance to do it with work etc I’ll finish early one day next week.
 
It was just a thought. I had the experience of using solvent glue on push-fit, where the adhesive went hard, but didn't meld into the pipe. The joint leaked after a while☹️.
I'm not knowledgeable about the different plastics, but I thought there were only some that solvent adhesive was suitable for.
Perhaps someone here could clarify?

Looking on the web it seems that push fit is typically made of polypropylene and solvent weld pipe is ABS. Polypropylene is not suitable for solvent adhesive, which must have been the reason for the problem I experienced!!
 
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