Soil pipe connection

[Tristar]

I have an underground (red in colour) soil pipe rising in a concreted ground floor toilet space to which I wish to connect the toilet, with provision for a sink waste as low as possible at the same outlet.

It has been suggested that the short, grey, boss pipe that I proposed to use, to allow the low sink waste connection, may not stick properly with solvent cement to the red pipe. Is this correct, and if so, is it permitted to connect the two with a silicone or some such similar adhesive?

It is not possible, without considerable work, to change the red pipe.


TIA

 

[denso13]

Solvent cement will be fine on orange underground pipe, if that's what it is. Orange underground pipe is just the same as the grey above ground - more or less.

 

[Tristar]

Unfortunately I've just found this link, suggesting I can't use solvent weld.

http://www.diydoctor.org.uk/forums/viewtopic.php?p=60372&sid=1aa5f83faaae5e1a191c2f599ec3db8e

However, I find it hard to believe that there is no form of adhesive that is acceptable to connect these two pipes.

 

[denso13]

Marley pipe and fittings, for example, are PVCu as are many others. They make a loose collar, UE400, which can only be solvent welded at one end, no other way of doing it.

 

[Tristar]

Unfortunately, I don't know what make the pipe is.

 

[Tristar]

Perhaps I could use this straight into the underground vertical pipe,
http://www.toolstation.com/shop/Plumbing/Pan+Connectors/d20/sd2887
and then strap a boss connector onto the pan connector for the sink waste.

Would this be acceptable practise?

 

[Hugh Jaleak]

AFAIK all underground stuff irrelevant of manufacturer is uPVC. Ring seal joints are used to allow flexibility in the joints. Ignore the advice in that link.

You wont fix a strap boss to a pan connector, pan connectors are polypropylene which wont solvent weld, and most are less than 110mm diameter anyway. Your original idea is probably going to be ok, simply need to glue a short piece of 110mm into the top of the boss pipe (if needed) to accept the pan connector. Make sure the pan connector doesnt go in too far so to foul the inlet from the boss connection though.

Alternatively, pan connectors are available with a 32mm boss connection already fitted, however this may sit too high to accept the proposed waste connection.

 

[Tristar]

Thanks very much Hugh, when you say my original idea, do you mean using silicone or WHY to fix the boss pipe to the drainage pipe?

 

[Hugh Jaleak]

Your idea to glue the short boss pipe to the underground drain. (Assuming the underground stub is uPVC of course! ) I cant see silicon making a good seal, solvent weld is the correct method.

 

[Tristar]

That is my problem Hugh, I don't think it is PVCu, it is the orange underground drainage pipe, make unknown, and is presumably why I was told that I shouldn't use solvent weld to join them.

 

[Hugh Jaleak]

If the underground pipe is plastic it'll be uPVC, I dont know of any that isn't! (Obviously if the drain was clayware then solvent adhesive is about as much use as a chocolate teapot....) If it dont stick together using solvent adhesive then come back and we'll have another think!

British Standard BS EN 1401-1 covers plastics for drainage, from what I can tell it covers uPVC.