Can anyone help figure out a route for this drain?

Naknah · 3 Mar 2017

It's an L-shaped terraced house. We're have a single storey extension built, filling in the side return and going out by a couple of meters, full-width. The extension goes over the drain. It's a private drain - serves just our house - and then connects in to the neighbour on the right. They won't agree to move it. We want to avoid an internal manhole.

The chap who is doing our drawings has suggested this. I've got two problems with it:
1 I'm worried that the length of drain running from the downstairs loo to the bend would be un-rodable. Would it be? Is there any other way to clear it?
2 I want the soil pipe from the bathroom to come down on the opposite side of the kitchen (see drawing). Is there any way to do that?
3 All of the kitchen plumbing will be on the other side of the kitchen.

Is there a better way to do it?

Naknah · 3 Mar 2017

After doing a bit of research, this is the way that I was thinking to do it but that bit under the house would be unroddable wouldn't it? And putting in a rodding point where I've drawn it wouldn't work because there'd be a bit of a bend where it joins the lateral drain - it's not just like a crossroads.

I read a thread on here that said a building control officer signed off on a similar plan because there are other ways of clearing a drain but I'm a bit uneasy about it.

Ian H · 3 Mar 2017

A rodding eye there would be useless. Is there a manhole off to the right in the neighbours garden?

If all the pipe work is all new then you would be very unlikely to have a blockage.

Naknah · 3 Mar 2017

Thank you for that. Yes there is and yes it would all be new. Are you saying we could do without rodding access?

^woody^ · 3 Mar 2017

How can you bring the soil pipe down on the other side of the house to the bathroom above?

If you are having the washing machine and sink where you have indicated, why hasn't your plan drawer put any drainage in there?

Pipes don't block on straight runs. They block at bends junctions and connections, and so that is where access points need to be. Your idea would will require an access cover in the floor where the drains meet.

wessex101 · 3 Mar 2017

Put the manhole where you've shown the rodding eye and offer the neighbour some cash to make a new connection to the drain in their garden?

If the neighbour is considering an extension of their own then go halves on relocating the main drain run. (and build a shared party wall astride the boundary for the extension to get rid of that annoying step in the wall)

Naknah · 3 Mar 2017

^woody^ said:
How can you bring the soil pipe down on the other side of the house to the bathroom above?

The bathroom is above where I've suggested the soil pipe goes, although the loo is half way between where I've drawn it and where he has drawn it so it has to be piped along a bit either way.

^woody^ said:
If you are having the washing machine and sink where you have indicated, why hasn't your plan drawer put any drainage in there?

I've asked him that question too!

^woody^ said:
Pipes don't block on straight runs. They block at bends junctions and connections, and so that is where access points need to be. Your idea would will require an access cover in the floor where the drains meet.

That's interesting about the location of the blockages. I guess it isn't good enough to be able to rod down from the manhole cover because there are still the connections on the other line where blockages could occur.

Is there any other way it could be done or am I stuck with an internal manhole cover?

Naknah · 3 Mar 2017

wessex101 said:
Put the manhole where you've shown the rodding eye and offer the neighbour some cash to make a new connection to the drain in their garden?

If the neighbour is considering an extension of their own then go halves on relocating the main drain run. (and build a shared party wall astride the boundary for the extension to get rid of that annoying step in the wall)

Unfortunately we are not on good terms with that neighbour - hence the step in rather than a new party wall. I have asked the question but didn't offer any money yet. Realistically I think pigs will be flying over the frozen gates of hell before they agree.

^woody^ · 3 Mar 2017

What is the existing drain layout? Is that toilet new or existing?

Naknah · 3 Mar 2017

This is the existing drains - drawn onto the drawings for the extension, I hope that isn't too confusing. The washing machine and sink etc. are below where the shower and bathroom sink are - so all the drainage from the kitchen runs along that side.

It would be a new toilet, located where the shower is on this drawing - we're looking to switch those two around.

^woody^ · 3 Mar 2017

I'd probably be inclined to go with something like your second image (post 2), omit the external IC and that rodding point, and install a sealed chamber internally.

And perhaps have a single wide radius channel bend in a brick chamber instead of a plastic pot, as this may give a smoother flow and removing the potential for unused points in a plastic pot and tight radius - allowing catch points for waste.

But a plastic pot may well be OK, and TBH few builders have the skill nowadays to construct a traditional brick chamber.

You're the end of a run and will have new drains, so the chance of ever getting a blockage is very very slim. So any internal IC lid will never be needed to be opened.

Your plan drawers initial idea is OK, but does not deal with your new kitchen connections, so I can't see how it works.

Naknah · 3 Mar 2017

Thank you very much for that. I was thinking to probably give up trying to avoid an internal chamber. We've got a single bend in a brick chamber at the moment and have had just the one blockage in 11 years of living here. I can't remember what that was. Anyway, thanks again.

Ian H · 3 Mar 2017

It would be fine without a chamber but you might have to have one because of the regs. If you didn't have a chamber, just a slow bend, the only place it would block would be where it connects back to clay after the bend.

A proper drain guy would CCTV the run and make sure the plastic to clay was perfectly aligned, that it holds no water and there are no displaced sealing rings.

Other than that you would want an access on your svp from upstairs and try and join your kitchen wastes in higher than the seat of the downstairs toilet. That way if you do get a blockage you will notice it in the toilet before your washing machine fills with ****e.

Naknah · 3 Mar 2017

That's interesting 1990. I can't decide now whether to try to get approval without the internal chamber. If you're saying it would only block at the join to clay, that's the bit that we could rod from the external manhole.

I'll check we're getting the upstairs SVP access. Unfortunately I think we're stuck with the kitchen wastes being below the toilet (there are two steps down into the kitchen). I did not know that could happen to a washing machine. And the dishwasher too? That thought is going to keep me awake at night...

^woody^ · 3 Mar 2017

You can't have a bend in a drain without a chamber.

diynot

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.

Are you a trade or supplier? You can create your listing free at DIYnot Local

Can anyone help figure out a route for this drain?

Similar threads