NEW Soil Stack

[ianm75]

Hi all,

Looking at replacing my old cast iron soil stack with a new UPVC one, partly in preperation for a downstairs toilet connection in future extension.

Should i cut the cast iron pipe for current up stairs toilet on outside leaving enough pipe to connect a rubber coupling? or should i cut the lip off the connection on the inside of the bathroom where the toilet goes into and pull the old pipe out and replace with new UPVC?

Also where it goes into the ground, should i again cut the cast iron a few inches from ground and join with another coupling or break up the surrounding concrete and replace with UPVC all the way.

Lastly if i did UPVC into the ground do i just cement in or do i need to seal first and then concrete,

Thanks

Ian

 

[dude_diy]

Hi Ian
As it happens ive just done a very similar change to my outside soil stack for a home extension with a new bathroom. To save on work for you and some money as well, there may be no need to remove the existing stack connection to your current bathroom and loo. Seems like your making work for yourself, unless of course you really want to change it all?

from what you have described I think the best job would be to just cut the current cast pipe above where you intend to fit your new loo and come off from there to connect your new toilet. Then connect it all back. So you will only need a Y shaped fitting.

As for going into the ground to connect up it seems again like a lot of work. If you do start going into the ground I would avoid cementing the new pipe as it could damage the pipe if it sets solid around it. Pipes usually need some flexability.

If you do start cutting into a section of a cast iron stack, make sure its wall fittings are secure. As they tend to work loose over the years. last thing you want is it all falling down on you.
Good luck mate

 

[ianm75]

Thanks Dude_diy for the reply.

I was looking at replacing completely because the old one is rusty and would need repainting anyway so thought it may be easier to use a chain cutter to remove and then replace with new UPVC. I understand the cost will be about £150 but also will mean less maintenance in the long run?

If however the replacement job is not that easy and may take longer and cost more than i think then maybe joining the old one is easier. Do you know any we links to the part erquired.

Cheers

Ian