connencting plastic to cast iron soil stack

[mike]

Bathroom renovation question again.

Since knocking the so-small-you-had-to-limbo-round-the-door separate WC and the every-so-tightly-packed we-managed-to-stuff-a-bog-in-here- too bathroom into one, we now have two toilets next to each other. I need to remove the one on the left of this picture and remake the connection to the one on the right:

The current connection seems to have been botched by gobbing up with, well, I'm not sure what. There also seems to me a mix of above ground and below ground fittings, assuming the brown colours are meant for underground drainage, so I hope I'm not opening a can of worms by trying to do the job properly rather than just buying a blanking plate for the tee.

Can anyone confirm that this is the correct connector for plastic to cast iron soil stack?

[Bob Minchin]

Brown fittings are for underground and also Ok for eleswhere where no sunlight can get at them. Black and grey have uv stabilsers in the plastic. That TS fitting looks like ones I've seen fitting into glazed clay pipes but provided the rubber bit make good tight contact in the CI should be OK but it looks like you have a CI socket so it might need to be a bigger version of the same type of fitting. That left hand bend seems to be fitted against the flow which is not conventional but no real difference to a coupler which always has one join facing against the flow, so it is probably OK. I doubt that the installation will give a problem but it looks crap.

I'd get rid of the CI y branch altogether, get the correct 2.5 degree drop into a new pvc Y branch fitted a little lower down and one of those TS fittings you show into the open end of CI pipe cut off nice and square. Do everything in black.

Bob

[harry]

The cast iron fitting probably had a lead pipe going into it from the WC pan in the past. The jointing method was to use putty and paint.

What Bob has said about brown fittings is right, they will deteriorate in the sun though you can paint them to prevent this. But the paint often flakes of after a while.

The joint seems to be misaligned where it goes into the CI branch. This might cause a problem. You can buy adjustable bends that form a bend of any angle by rotating the parts. I would say just use the putty and paint method to joint the plastic to the cast iron socket.

[Tim Watts]

On Friday 05 April 2013 11:04 mike wrote in uk.d-i-y:

It's been bodged. The angle of the tee into the main pipe is such that it would probably meet the right hand toilet at a steeper angle.

The pipe has been laid nearly horizontal to allow the 2nd bog on the left to be connected in.

Redo the short run and it should look (and conenct) a lot better.

[Andrew Gabriel]

If you can find it, use top coat gloss paint directly on PVC (no undercoat), high in volatiles type (not made for some years, but if you have an old can of gloss top coat, that's the stuff).

It won't flake off, because the paint solvent dissolves into the PVC surface. (It will work as solvent weld too.)

If you need to make a new PVC pipe/gutter look like an old cast iron one, ladle the paint on thick, with the odd run in it.

I haven't tried using the new low volatile gloss paint on PVC, and I would be interested to know if it works as well.

[mike]

Thanks for all the suggestions. Will redo in black. Just considering whether to cut the CI back to near ground level while I'm at it...