House purchase: built over drain inspection chamber?

freeof1

Hi all

Would appreciate a bit of advice with a house we're looking to purchase.

Semi detached house had an attached garage that was converted into a side extension, which now goes all the way along the side of the house (the garage presumably would have only gone halfway or so along the side of the house - similar to this floor plan https://s3.eu-west-2.amazonaws.com/standoutproperty/Media/20ef5f60-732e-4d2d-8a06-f24dc24eda95/c8328e97-f675-4989-89b3-cc120b25935c/GRM-131310DT_3700544931.jpg) .

The surveyor noted that he couldn't find the inspection chamber, possibly because it was built over by the extension.

We want to know whether this is true, and if so whether it was allowed, and if so what the worst case scenario is for us.

We've asked the sellers but they've only said this: "The drains immediately lead next door from the point where our downstairs toilet is situated, and where there is a soil pipe is which could potentially be rodded at least to the extent of any issues within our boundary. The drains combine with neighbouring house and run to the road in pairs. There is an inspection cover in the next door property. Whilst this is not ideal, this is the way that the houses were built at the time. In reality would be more of a problem for next door neighbour than for us since any blockages downstream from us would be in our neighbour's property."

Thus far they haven't provided any completion certificate or similar.

FYI the downstairs toilet they refer to forms part of the side extension but is located behind the old garage ie at one point would have been open air (in the floor plan above the toilet is now behind the garage in that open 'square') so theoretically there was an inspection chamber which has been built over.

Any advice on how to clarify the issue and what we need to be requesting?

Even if things were all signed off according to regs what risks are we opening ourselves up to if our inspection chamber has been built over?

Many thanks

naf123

If it's a shared drain it could be outside your land . A solicitor water search will confirm this .

The question boils down to whether there is an actual private drain for the property itself . If toilet so close to boundary it's possible the actual drain is shared with next door . Private drains won't come up on solicitor water searches

You could knock on next door and ask them ;-)

MoLatif

Worth checking that the extension didnt breach any restrictive covenenants (not considered during planning applications). Our house has such a covenant, preventing extensions as the drains run right up against the rear of the house. Previously decking had been installed which prevented access for inspection and my conveyancing solicitor said I would be required to rip it up if access was required. Not such a big deal for a bit of decking, but an extension on the other hand...

If there is a restricted convenant and permission from the holder wasnt given, they could turn up out of the blue and have you take it down. Worth checking for peace of mind.

Mistral001

The vendor has given a very detailed answer to your question. They explain that the inspection chamber for your sewer pipe is on their side of the boundary. That means that if there were a blockage in your sewer pipe you would have to rely on the neighbour giving you permission to rod the pipe from the manhole on their property.

The problem could be solved by constructing an inspection chamber between your downstairs toilet and the boundary. That means that you will have access for rodding without having to depend on your neighbour's permission to get access to the inspection chamber on their property. I would get that the construction a new inspection chamber priced and try to negotiate a reduction in the cost with the vendor.

I would also get professional legal and architectural advice to establish that what the vendor is saying is correct and that there are not any other problems with this sewer pipe.

freeof1

Thanks for the advice.

I'll make sure our solicitor checks about any restricted covenants. That would be a pain if there are but better to catch it before we buy!

There's no chance of being able to install a new inspection chamber as the side extension butts up to the boundary so there's no space to put it.

I spoke to someone at Thames Water today and they advised me firstly to request a build over agreement via the solicitor. This should have been granted when they built the extension. If they don't have one then we could apply for one retrospectively and they're granted in most cases.

Secondly, he said most houses do have their own inspection chamber despite sharing a drain that runs on the neighbours property. So the fact this house doesn't have a visible inspection chamber probably means it was built over by the extension and is currently sitting under the floor.

His interpretation of the owner's reference to the soil pipe was that there is an access hatch in the pipe above ground that can be rodded to unblock the soil pipe within our boundary. But that is separate to the inspection chamber, and that the only accessible inspection chamber appears to be in the neighbour's garden so in case of any blockage to our drains we'd need to unlock them via their inspection chamber.

I've asked the owner flat out if there is an inspection chamber below the extension. Either way we need to make sure we get on well with our new neighbours!

freeof1

So I've accessed the architect plans online:

(yellow corner shows the external corner of the original building footprint, and blue identifies info relating to drainage etc.



It looks like the inspection chamber is in the kitchen (where it says "New IC"). That seems unusual and I'm surprised the surveyor didn't notice it.

Plus the soil stack and soil ventilation pipe (svp) are now internal. I need to check how that ties in with the owner saying the soil stack can be rodded. Wouldn't like to be rodding the soil stack from an internal access point!

Also looks like they removed the original gully and I don't see evidence in the drawings of them replacing it. Not the worst thing in the world but worth noting.

Have I misinterpreted anything?!