PVC into Cast iron soil pipe - replace the whole pipe or just a section?

[Gaz-DIY]

I have a quick question!

I have a cast iron soil pipe (number 2 below) that I want to join a PVC 110mm pipe into (number 1 below).

What I’m not sure of is;

Do I have to get a cast iron branch junction or will PVC do if I support the cast pipe above and below with the proper brackets and use SP140 to join then?

Or does the branch junction I’m putting in have to be cast iron because the soil pipe above it and below it is?

I would like to keep the cast iron pipe above and below my new join (number 2) to save me from replacing the whole pipe from above ground to the guttering as it will be a lot more work and look out of place with the cast iron pipe just to the right of this pipe, that you can’t see from this pic!

Thanks in advance.

Gaz

 

[Hugh Jaleak]

You can use a plastic junction, but do not underestimate the weight of the cast above it. (It'll probably still look odd though, plastic is considerably thinner than cast!) It is vital the cast above is adequately supported, if it falls it will do some damage!

 

[Gaz-DIY]

Thanks Hugh Jaleak, good point about the weight of the cast pipe.
Not sure whether to replace all the pipe with cast effect (£40 branch, 2 x 2,5m £60 = £100) or just the branch cast section (£??)

Thanks again.

 

[Bosswhite]

Rip down the old cast iron replace with PVC to junction ( minimum), not going to cost a fortune and will be more safer in the long run.
To try and cut into the old cast iron pipe with PVC will be more trouble than its worth .

 

[dilalio]

Rip down the old cast iron replace with PVC to junction ( minimum), not going to cost a fortune and will be more safer in the long run.
To try and cut into the old cast iron pipe with PVC will be more trouble than its worth .

+1.
Check the back of the cast iron throughout the system... It may be almost rusted through and the decision to replace made for you