40mm waste to existing imperial soil stack.

[burb mac]

Hi folks,
I am going to replace kitchen sink waste pipe with metric. This however feeds into an imperial soil stack. Last time I did this I found the smaller metric pipe didn’t seal properly. What’s the correct procedure?
Thanks in advance.

 

[PlumbBobBob]

i think i would be inclined to use a compression coupler and cut the pipe leaving the imperial pipe in the soil stack and connect the new pipe with the coupler

steve

 

[burb mac]

i think i would be inclined to use a compression coupler and cut the pipe leaving the imperial pipe in the soil stack and connect the new pipe with the coupler

steve

Thanks Steve for the reply.
On further investigation I wonder if the existing pipe is 50mm and not imperial. Never knew they existed, never seen them in DIY stores!
I note from going on proper plumbers merchants websites that you can get a 50mm to 40 mm adapter, never seen them in the stores either!
You would think these items would be in demand and available from the stores that seem to sell the lot!
Apparently not!
Thanks again.
Bob

 

[tamz]

The big sheds carry a very limited selection of plumbing and heating fittings indead some manufacturers refuse to supply to them.