Kitchen Sink Problem

Jeepers_Creepers

Have you sketched a plan of the layout and manholes covers yet? Care to share it?!

Is there any chance that the main sewer bends round and goes down the side of your house - perhaps even on the neighbouring land - and the original drain headed off left or right towards this?

When the guys did the CCTVing, how far down that visible waste pipe did they get? These fittings are solvent-welded so cannot just be pulled apart, so I suspect that either you (if you are DIYing) or your new plumber will need to cut the end where it straightens up to head through the floor - it'll be easy to add a new union afterwards. I would then hope that whatever is used to probe/investigate - unblocking cable or camera - will get much further down there.

If that fails, then perhaps swapping between a flushing hose and extraction will gradually work its way through whatever is causing the blockage.

What a 'mare, but actually a good chance that the builder wasn't a complete cowboy and the drain will actually be located and found to be somewhere 'sensible' - if currently hidden...

Jeepers_Creepers

When was the extension built? Who was the builder - the previous owner must surely know? He doesn't have to still be in business - just alive!

ac198179

I have a big update! As I've mentioned before, the house has been re-modelled several times over the years including at least 2 extensions. I've got copies of most of the plans of the extensions including multiple copies of the same documents - or so I thought! I have 2 copies of the plans for one of the extensions and I always thought they were the exact same document - from a quick glance they look the same only 1 copy has a manhole and a drain line marked on that I never knew about! The drain line runs from where our kitchen sink is to this manhole. I've been outside and physically found this manhole which is between our rear extension and my neighbours rear extension (very small gap between the buildings). Now that I've found this, I've got the drainage company coming back on Monday to have another go/investigate further. I'll report back after that! Only drawback is that the panelled fence between myself and my neighbour is on top of the manhole, but he's happy for me to lift the offending panel out of the week ready for the drainage people.

Jeepers_Creepers

Yay! Happy new slurry-free drain.

Apodemus

Good to hear that, thanks for providing the update!

ac198179

An update...the drainage company came back yesterday and investigated from the inspection chamber that I had found. The kitchen sink does indeed drain into it through a 100mm clay pipe....which they think has collapsed from looking at the CCTV Only option now really is to dig up the floor inside which will probably cost £10k - the glued down flooring will have to be replaced as well as taking out the whole kitchen as that's on top of the flooring. There are some other options involving a macerator and running a 21mm pipe from it to a new gulley outside (by running the 21mm pipe behind the kitchen cupboards and out of the external wall) but obviously the best solution is a dig up. I've asked them about drain re-lining but they said no to that.

GDB2222

Oh dear! I can’t really say anything useful here, except think about the macerator and different routes for the pipe, including going upwards and into a bathroom drain.

Jeepers_Creepers

It can't be bored out from the inspection pit and sleeved?

ac198179

Jeepers_Creepers said:

It can't be bored out from the inspection pit and sleeved?

Not according to the drainage company (it's a local firm BTW, not one of the national franchises). I think one of the problems is that the 40mm white plastic pipe from the sink disappears into the concrete floor so it wouldn't be possible to solidly connect it to a new 100mm drain pipe from a distance. I think I'm going to get another drainage company to come out as a second opinion - I think it's worth me spending another £100/£150 for another CCTV survey just to make sure.

GDB2222

Surely, if a relatively recent drain has collapsed, there must be an underlying issue that caused that. Perhaps it wasn't laid on a proper foundation. How would a sleeve solve that? Won't it just keep moving?