Converting push fit to glued?

[mattylad]

So in my new bathroom the guys fitting it did an amazing job, not finishing until 9pm on one evening (they are returning after xmas) so that we had facilities over xmas and I'm not knocking them.

However the final outlets for the shower and basin go via a 38mm ish and 40mm pipes.
The one on the right is the shower at 40mm, the one on the left is the 38mm ish (not entirely sure) from the basin.
The shower white to grey joint to me looks very suspect and did leak at first, to me it's not straight.

FYI this is a view from underneath (where part of the kitchen ceiling fell down due to a leak).

What I'm thinking is that once the ceiling is repaired, there will be no further access to these joints so if they leak again I'm stuffed.
So what I'd like to do is convert them to glued fittings.

So first off can I get a 40mm 90 angle that will glue onto the shower PVC pipe top right?
Then I can change the whole pipe through to the outside and use glued fittings out there too.

Same with the smaller one on the left?

All I can see at screwfix are packs of 5 of each type of fitting so I'm hesitant to use them, I may have to have a trip to wicks/b&q instead.

 

[denso13]

Toolstation do them in singles, as long as it isn't push fit pipe, that won't glue.

Maybe use compression fittings, which shouldn't come apart

 

[foxhole]

Those are pushfit which use different size pipework to solvent weld.
Compression will fit either so you need them unless you replace the pipework as well.

 

[Hugh Jaleak]

Sorry, but no professional Plumber would use Push Fit, never mind under a floor where it cant be got to. Solvent Weld every time, done properly will never leak. I certainly would not want Push Fit under a floor!

Basin will probably be 32mm, shower should be 40mm. The grey section of 40mm pipe on the right does look suspiciously like the right colour to be solvent weld, although I am slightly concerned, as Foxhole has said, Solvent Weld and Push Fit waste pipe and fittings are not compatible, and the only method to join the two types is with a Compression joint.

Push Fit fittings cannot be used on ABS (Solvent Weld) pipe and vice versa, as Push Fit is made from Polypropylene, which has different characteristics and solvent weld adhesive wont melt it. If they have used a Push Fit Coupler to try and join to Solvent pipework, then sadly I think they are asking for trouble.

Bear in mind if you replace, (and I think it is really the only safe option to guard against future issues), you will need to replace the pipework and fittings all the way through, all the Push Fit stuff that they've installed will need to come out.

 

[Madrab]

Unfortunately, I think the problem here is that they could be bathroom fitters? Whilst not all are the same and your chaps may be good workers, I find that a lot of them are a jack of all and unfortunately a master of none and I find myself repairing a lot of their work when it ultimately fails.

As @Hugh Jaleak has mentioned, no self respecting professional would ever use push fit waste pipe, especially under a floor, it really is a host or problems waiting to happen. Worst case really would be to use compression and whilst it is far more secure than push fit, the proper approach would always be solvent weld.
You need to test the grey pipe to see if it's is ABS and see if it can be Solvent Welded(SW), alternatively a good quality compression coupler (McAlpine) could be used to transition.
As suggested though, there are really only 2 correct options really. First one is do it properly and replace it all with SW ABS, the other which would at least be safer than what is there at the moment is to replace all the push fit couplers with compression couplers.

How finished is the bathroom floor, can it still come up to expose the pipework?

 

[aveatry]

I have some push fit that I have installed myself under the shower and bath but I made sure it was accessible as the bath panel can come off as can the side of the raised shower tray. So what can happen to push fit, will the rubber o ring eventually degrade, or I dont see how it can un-push itsself when all the other pipework is keeping it pushed in.

 

[SithLordHood]

If push fit is that crap, why the hell is it sold? I did my bathroom sink and shower waste with push fit a few years back and it has been fine so far…

 

[CountryFan]

If push fit is that crap, why the hell is it sold? I did my bathroom sink and shower waste with push fit a few years back and it has been fine so far…

It isn’t crap. We have used it for years, possibly due to maintenance purposes, no idea why, but I have found solvent weld to be a pain sometimes.

 

[aveatry]

If push fit is that crap, why the hell is it sold? I did my bathroom sink and shower waste with push fit a few years back and it has been fine so far…

I suppose there are many things sold that are not fit for purpose but I am genuinely interested as to why they are so bad and how they can fail.
I know they suffer badly from uv damage but whats the harm indoors.

 

[SithLordHood]

As you say, UV not an issue when it’s all buried in floorboards.

I hear similar comments regarding speedfit/etc fittings for central heating. Used for 15ish years in all three of my houses I’ve owned and never had a problem.

 

[denso13]

If push fit is that crap,

It isn't. Just piece of mind that solvent weld gives a more secure joint in places which will be covered up and hidden.

 

[denso13]

I hear similar comments regarding speedfit/etc fittings for central heating

From who? I don't mind using speedfit.

 

[Hugh Jaleak]

I think it is like a lot of things, if installed to the letter of the book there probably wont ever be a problem, but invariably for many reasons, things aren't, corners are cut, and by the time it all goes wrong, the installer is long gone and not answerable for the issue.

Push Fit (Polypropylene) has different characteristics to the ABS stuff, it can handle higher temperature discharges however, it also needs proper support otherwise it can sag, in some cases quite badly, especially after a discharge of hot water, which will soften the plastic. Should it not be adequately supported, there is the potential for the sagging to eventually cause the joints to fail and leak. Not ideal when buried under a floor...

 

[Madrab]

For me it's a few things. Most of which I have experienced.

Solvent weld is a bit like soldering copper, once it's glued properly then it can be considered part of the pipe and from a secure and low leak risk point of view, there isn't a better approach. Therefore there should be no need for a properly set out waste run to be created in anything else but the most secure method, which is SW IMO.
Push fit is also an effective DIY approach to creating waste runs and that is another market that is too lucrative to manufacturers to ignore but if I saw a professional choosing to install push fit then I'd be a little wary, as it has inherent weak points that the other 2 methods don't.
When it comes to clearing blockages it can be very susceptible to detaching when either using mechanical tools like screws/worms/rodding and pressure clearing like plungers/power plungers and of course jetting. Taking the picture above as an example, straight off that right hand elbow could be knocked or blown off quite easily.
When working on any of that pipework upstream, without knowing it was pushfit, then it could be possible to disconnecting a fitting on the run without realising it when manipulating the pipework. Invariably as in that install, there is no pipe clipping on either plane, therefore could be pulled/twisted apart quite easily.
Over time the seals can harden and then leak, especially if there is a blockage and the pipe sags, the joints could then fail under the pressure/weight of the water.

To me that's many possibilities for potential issues and call backs, when the more secure methods are easily used.

@mattylad , am I correct that it was the pushfit that leaked and brought that bit of the ceiling down?