We had two quotes for work refitting our bathroom and adjacent separate toilet. One involved replacing the existing internal cast-iron soil pipe with a new external pipe and the other did not (suggested by the second person to quote). Clearly not removing the existing SP is easiest, but making the change is preferable for several reasons and obviously involves different routing of pipes, connection to the drains and removal of the old pipe.
The difference between the quotes was over 3K.
I thought I'd ask if anyone can advise how difficult this might be? As a layman and not an enthusiastic DIYer, I can't see it being too tricky, but you guys might think differently.
The existing soil pipe runs vertically from roof (it goes through the roof space and out through the tiles), through the bathroom and down into the kitchen. The WC is adjacent to the bathroom and the waste pipe must run between the two rooms via the floor space.
The SP is not visible in the WC - it emerges from the floorboards. In the kitchen and bathroom it's boxed in. In the bathroom the bath and sink must feed into it (the pipes enter the boxwork around the pipe).
The house was built in the 60's. I've no idea how the SP is coupled to the outside pipework, which I'd assume are clay pipes. I'd imagine I'd be looking at fitting a new bend/junction to replace the pipe as it currently enters the house and attaching a new vertical pipe to that. The pipe would continue vertically upwards where it would meet the roof and I'd either have to run it through the roof (there's an overhang) or around the roof (ugly).
To meet the toilet, I'd need to have a horizontal(ish) section of a few feet to go into the separate WC. The bath and sink waste could exit directly through the exterior wall and feed into the soil pipe, rather that running around inside the bathroom as at present.
In terms of logistics, I would imagine that I could dig out the area around the existing soil pipe to ensure I had the correct connections.
On the day of the replacement, I could fit the exterior soil pipe, run the soil into the WC and fit the new WC. I would have to remove at least part of the existing SP to do that (the part that connects the current WC to the soil pipe).
I could reroute the existing bathroom waste into the new soil pipe (I guess I could do that partly in advance - we have an exterior drain, so a long pipe would do the job until I set up the new SP properly).
Next would be extending the SP through or around the roof. Connecting up the sink/bath waste to the new soil pipe and finally removing the old pipe.
I suspect that removing the old pipe might be a bit of fun. I'll need to replace some roof times to sort out the hole that would be left.
Anyone already done all this? Is it really difficult? How long did it take? Any good reference sites/materials to advise on this work?
Should I just cough up?
I'm not an enthusiastic DIYer, about as enthusiastic as the builders that take weeks to come up with quotes.. and wondering if this can really be 3K worth of work..
..however, In a week or so I'm off on a bricklaying course to see if I can do some work myself (extend the garage, do a new garden wall, etc..).
I await responses with trepidation!