Foul Drain Solutions

[DarrenSL]

We have had a new extension built at the back of our house. Unfortunately the builder didn't read the plans properly and mucked up the gulley and concreted over (piled, ring beam and slab). We are now left with no kitchen foul drain.

Worse still, we don't have any private drains to plumb in to

View media item 50041

I think we are left with the 3 following options (unless anyone has any better ideas):
1. Hack up the concrete kitchen floor and lay 40mm waste pipe under the floor to the soil stack
2. lay new drains into the public sewer (approx 10 mtrs away and 3 mtr deep on public footpath) OR back public sewer may be on my land but again are 3mtrs deep and under 30ft conifers.
3. plumb into neighbours drain (although she has already said 'over her dead body' are we digging up her garden). We may get lucky here if the drain passes over my land as I suspect it lies close to the border.

How much very roughly would it be to lay new drains into the public sewer? Is the 40mm pipe under the kitchen floor an acceptable solution (i.e. would I be harsh to expect the builder to rectify the problem by laying into the public sewer instead)?

Any help would be much appreciated. Thanks.

 

[haronel]

if you can trace where the pipe goes out of extension you could build a new manhole to take your waste,providing its on your land. other than that the least expensive would be to take up the floor but then you would possibly need an internal double sealed manhole cover but as it is only sink waste maybe not

 

[DarrenSL]

Thanks Haronel.

I have about 1mtr between the house and boundary where the existing drain passes. This would be a perfect solution for me but wouldn't I have problems with Building Control for having too many/too tight bends?

 

[haronel]

i gather you mean because of the depth. speak to building control ask them if its ok to build the new manhole and enter the waste pipe higher up. if its only sink waste i cant see a problem. good luck

 

[DarrenSL]

No I was thinking about bending from the kitchen round corners. The kitchen is at the back on the left side of the 'house' in the diagram (next to the old gully where the drainage starts). The drains would need to go out into the garden, across the back of the extension and then double back through a 90 degree turn (or 2x 45 degree bends) and then down a 3 mtr drop shaft.

Everything else has been signed off by BC so it would be a shame if I couldn't get a completion certificate because of this.

My understanding was that drains have to be roughly in a straight line (slight bends acceptable) joining other drains at oblique angles.

 

[Nige F]

You should be ok with that - with a Rodding point and roddable gulley - have a look @ , say Osma drainage , simple idea , commonly used - check with the BCO

 

[jeds]

Have you not asked your builder what he proposes doing about it?

 

[noseall]

Unbelievable that at no point did the client or the builder or anyone else stop and think "....er anyone considered what we are going to do with the kitchen waste....!"

I find this story even more astonishing given the difficulty involved in rectifying. This should have flagged up at the groundwork stage and is bordering on the bizarre that no one gave it a thought.

 

[DarrenSL]

This was actually flagged up on numerous occasions. I had it specifically drawn into the plans and also spoke directly to the builder when I saw them smashing the gulley and re-directing the polypipe into a surface water drain! I was told not to worry and everything was in hand.

Now we are in this situation I have written a formal letter to the builder stating negligence and withholding payment until the problem is rectified.

In the meantime we continue to dig (as we have for the past 3 weeks) looking for the drain

There are a couple of mitigating factors however:
1. The existing kitchen gulley is actually attached to the surface water. Presumably when the kitchen extension was built 30 years ago they couldn't find the drain either. It was 3 years ago that this problem was identified (by the EA) so I had 3m 40mm pipe running round the corner into the foul gulley. This is the reason I had the replumbing added to the plans.
2. According to the local authority the drain runs along the back of the houses. We now know that in 1974 the drain collapsed and was diverted to the back sewer.

Its a nightmare. Maybe this should be moved into the 'disasters' section of the forum

 

[DarrenSL]

Check out the waste pipe. What an eyesore. Should have been a clue I think

View media item 50143

Looks a lot better now though

View media item 50145
Shame about the garden

View media item 50144 View media item 50146

Thanks for all the replies everyone.