Soil stack alterations

[marsaday]

I am going to add another toilet in my attic. I am also moving my toilet on the first floor closer to the soil stack.

1) Can i get my soil stack rebuilt before i put in the horizontal connections to each toilet. or is it best to build the soil stack to the first outlet and get that in and then build up again and get the second connection in ?

2) What is the best hole size to core out ? Is 110mm ok ? or should i go for 150mm ?

3) i have at the top of the soil stack a whole piece of cast still. I will need to cut into this to fit my new 2nd toilet. Should i dismantle my soil stack in plastic lower down before i do this so i dont get any bits in the stack (put a lid on it while doing the cutting).

4) Whenb reconnecting up to this cast piece do i use a slip coupling to get the stack into place ?

 

[justlead1]

Hi.No.1 Providing you work out the required fall on soil pipe run from proposed WC. position. Putting up the stack and branches shoud not be a problem.
2. 150 mm gives a bit of room and allows for any collars that might clash with wall.
3. Difficult with out seeing but perhaps replacing the top section of the stack with plastic may be a better option. If only to relieve the plastic stack from being the bearer of the cast iron mass in the event of fixing failure.

 

[marsaday]

Thanks.

The problem with removing the full cast iron is that it goes throught the eaves section and then through the roof. I can do all this work, but it will be eaier to leave the cast in place. It will have one cast bracket holding it on the wall and then it goes through the eaves and this is also holding it in place some what.

I have a tower scaffold up ready to do the work, so do you think i should remove the cast fully ?

 

[gates1979]

Your better off removing all the cast and do it all in plastic its a bit more work for you but while you have the scaffold up you might as well do the lot than do half a job then have problems in the future

 

[Centralheatking]

With cast pipe once you start mucking about with it it tends to break/leak quite a long way from where your working - because i suppose its so ridgid/brittle. So I would replace all with plastic.

centralheatking

 

[marsaday]

right i will try and replace fully