Prehistoric solvent weld pipe?

[Martin Brown]

I have in the process of removing my mum's old bath to install a shower run into an interesting and as yet unresolved conundrum with the waste pipes. They are grey and approximately the dimensions of modern solvent weld pipe at 43.7mm (bath) and 36.5mm (sink) respectively.

(ie the old pipes will not fit into modern solvent weld fittings for

43mm and 36mm)

I am sure of the measurements. Are these some old weird Imperial size since metricated to 43mm and 36mm or has the old pipe swelled with age?

According to this lot the pipe size I have encountered does not exist!

If Imperial they would be ODs of 1 23/32" and 1 7/16" respectively.

Now for the gotcha - they appear to have push fit connectors on them and the sink waste takes an insane number (5) of right angle connectors to get from the wall to the sink. I dare not tweak it in case it is actually solvent weld, but the connectors on the pipe run look exactly like modern O ring seal push fit except for being about 4mm bigger!

Anyone recognise this size? I could in theory bridge the old and the new with a universal compression fitting but as ever space is tight.

My options as I see it are roughly to either find a compatible set of new fittings and pipe or redo the whole lot. I estimate that the installation was done in the late 1970's if that narrows the field any. How long does this stuff last?

BTW thanks to all for the tips on blanking off the supply pipes and getting the old bath out. I junked the taps in the end.

The old bath turned out to be nearly 10mm thick acrylic with a thin glass fibre reinforcement on a tubular steel frame with MDF baseboard and then surrounded by heavy wood subframe screwed into the wall by two hidden 2" wide stainless steel brackets that made it incredibly rigid. The latter only became obvious when all the visible fixings were removed and it still would not budge an inch!

[The Natural Philosopher]

Redo the whole lot frankly.

modern solvent weld goes together like lego, and its not hard when you have an existing installation to buy the correct parts in advance

And I don't recall plastic pipe and connectors as being bank breaking stuff.

Almost every time I have tried to save by reusing old s**te, I ended up spending hours and wasting money.

[harryagain]

Waste pipe sizes vary a lot between manufacturers and often aren't interchangable. There used to be push fittings that had an O ring seal too, you never see them now. They often leak if messed about with.

You'll be lucky to find something that matches old systems IME The one get out is to use the compression fitting(s).

You can get mucked about even with the glue. Some pipe is made of PVC some is polythene and some is ABS. Not all glues work with all plastics.

[Martin Brown]

That is reassuring. I have never seriously used solvent weld pipe before as I have generally found push fit easier to work with. In this tight space though the narrower profile of solvent weld fittings would help but I am a bit wary of their highly irreversible nature.

Although I am not sure I would do it the same way as the existing installation which essentially goes

*- wash basin drain / / (long) *====* / * |

--------* (very long ie length of bath)

• is a right angled bend fitting

All the others are almost as short a piece of pipe as will fit and the one marked with "====" is sloping the wrong way for correct waste flow :(

My proposed solution would be along the lines of *- / / o----* /

--------o

o is a 45 degree bend

I suspect everything has perished (based on what the bath seal looked like) so that the instant anything gets moved or knocked I will have to redo it all anyway.

Should I also get a new plughole assembly for the sink itself and are there any likely Imperial metric incompatibilities to watch out for there ? I'd like to get it all finished on the next visit...

It isn't that bit that worries me it is breaking the bit that goes through the wall and then having to work at height on the outside.

Also the new stuff all seems to be white and it strikes me that black plastic waste pipe would be a lot more resilient in an exterior position (I know it says paint exterior waste pipes to protect them).

That is what I am afraid of. Also I suspect that the insane number of right angle joints in the wash basin pipe indicates some sort of problem with degrees of freedom of movement leading to having to put many bogus connectors in just to get the thing installed.

Obviously there was a huge amount more space under the corner of the bath than there will be under a shower tray platform. I was hoping not to have to meddle with the existing wash basin and to connect the bath to the original but it looks like it will be safer to redo it all.

[The Natural Philosopher]

just get all new everything otherwise its endless buggering about

solvent weld with gooey solvent gives you about ten seconds to get it all lined up, so assemble dry first, and work out which bits you do first and how to get the last bit on place

[polygonum]

I found flexible waste a boon in one particularly awkward place. Such as HepFlex waste:

You can't leave it unsupported as it sags, but it is tough and, IMHO, easy to use. The solvent weld of the spigots is easy as you do it wherever is convenient rather than in situ.

Seems expensive - can't remember it being that much...

[Dave Liquorice]

Or make up a section as required and join it into the system with a universal connector(s)(*) so it can be removed later to unblock it.

(*) Pushfit would be nicer but I can never remember the pipe sizes/compatibilties between solvent weld/pushfit.

[Martin Brown]

Thanks for the pointers guys!

I managed to get that bit done and to my immense surprise it didn't leak! I used pushfit in the end as the access was too fiddly to risk having to get it all together at 10s per joint with solvent weld.

The hard bit was removing the outer parts which included push fit components cemented (actually more like rice grain concreted) into the outer wall and at height. Incidentally Aldi has its last few 3 stage

4.7m ladders on offer and it will just fit in a decent sized car.

The original was definitely slightly larger than modern solvent weld pipe but with push fit fittings on it. I will scrape the paint off them and try to find any identifying marks when I have time to spare.

Next weekend is the truly scary bit of attaching the main waste to the shower tray and bedding it in cement mortar on the 18mm marine ply. Any practical tips on the best way to do it with least mess?