cast iron stack system

[pauls]

been to look at a leaking stack system its an old external cast iron the leak has been there for sometime as all the brickwork has gone white its where the soil pipe comes out of the wall and down to the stack.

to fix it i can only see the whole system would need replacing. not to sure of how to go about removing the old from inside through to the out side has anyone done this type of job before

 

[danielp]

the best way is to get a scaffhold and gloves and a big hammer start from the top breaking it, where the soil pipe comes out of the ground cut a little way up with a reciprocating saw so its a nice straight edge and use a rubber cast iron to soil pipe connecters they are rubber with a jubilee clip either end then just renew the lot

 

[REDSAW]

DANIELP, means a slip collar. stick a grinder thro the c/irn pipe 6'' from ground level, go up with plastic pipe. smash out pipe from cavity renew and point of when finished.
if u dont or havnt done one before....good luck.

 

[Puddle]

Hi pauls

Danielp,Redsaw34 and yourself are right, it is better to replace all the soil pipework if possible as it corrodes through at the back were it has not be protected /painted
Soil pipe is not that expensive any more, you can get in black, saves painting and looks good
The hardest part of the job is removing old cast through wall, so cost wise looks better replacing all than just a section
But is a two man job, the old cast is heavy so be careful and do not try to take down to big a section at a time,even if you get away with it ,you will only save 1/2 hour
Just a thought make sure leak is not an old lead overflow cut to short

 

[NickH]

Couple of tips pauls,

Defo a two man job, as you break the old cast pipe some bits will fall inside so lift the next manhole cover and fish them out, might have to flush them out with a bucket or two of water.
When you cut the bottom of the stack, unless you have a monster grinder you wont get right through so, cut as far as you can then cut again about 4 inches higher and remove the section between the cuts , you can then get the grinder "inside" the pipe to cut the back , dont be tempted to "snap" the cast iron, i've seen it crack down the length and below the ground, big trouble there.
Good luck its a job worth doing and much easier than it looks.

 

[REDSAW]

slice a grinder thru and push a piece of ply in slot made saves fishing out debris from drain, a proper 'mans' grinder 8'' no prob.

 

[Bernie2]

Err! Is it a whole new stack or just replacing the WC bend?

The bends are usually lead with a soldered ferrule at one end for jointing into the cast and a thimble at the other to take the pan outlet. Unless, its the likes of a conservation area and you are required to swap like for like. I would just take it out right up to the branch and renew in PVC, not forgetting to put expansion allowance on the insertion depth. I don't know what size cast it is, but on 3/16" the plastic usually goes right into the branch socket or you could get cast to PVC adaptor to do the same thing, looks a better job.

But as usual depends how much room you have got to get an adaptor on. Sometimes the bend through the wall is so tight against the cast all you can do is get the spigot of the bend into the branch socket.

The problem then is getting the caulk to stick to the plastic. One trick was to measure the socket depth, then coat the bend spigot with solvent weld adhesive and throw sand on it to make the bottom of the bend look as though it had been surfaced with sand paper. Actually I think it was an official PVC makers tip not one made up by the lads. Anyway this provides a surface to stick the likes of PC4 caulking compound too or even I suppose Plumbers Mait after a couple of turns of gaskin to dry caulk it first.

Hope this helps or at least gives some ideas.

 

[pauls]

cheers fellas thanks for the replys plenty to think about there