Collapsed drain under house - any advice?

[Overeggedit]

Hi,
I don’t know if anyone can help with this. I live in a mid terrace Edwardian house, and extended out the back about five years ago. Recently had a rat problem, and during a drain survey to find out how they’re getting in it’s become apparent that none of our waste water is draining into the main sewer.

It seems like one of the old clay pipes has collapsed under the extension.

If it’s under the extension, how do I get it fixed? Do I have to have the floor ripped up to do it?

What do I do if all the waste has been pooling under the house? How much damage could’ve been caused? I don’t know how long this could’ve been going on for - the only problem we had was rats - no smell or problems aside from that.

What sort of amounts could this cost me...?

Anyone with any similar experience or tips, I’d really appreciate it, thanks so much x

Have you spoken to your insurance company? They should be able to advise...

Agree with PP - sounds like a case for your home insurance.

I would say 750 - 2000 but I'm not sure without knowing the details. It also depends on different factors; would you need to replace an expensive floor finish, do you have underfloor heating, how many metres of the pipe are broken etc.

Sometimes you can leave the broken pipe in situ and add a new one outside of the house but I don't know if that's possible in a mid-terrace; it depends on how the drainage in your house works.

I'd get it done as soon as you can because you wouldn't want your new extension moving due to the sludge under the floor slab/foundations. But don't worry about it too much until someone's had a proper look and can see what is going on; get some quotes and give your insurance a call.

Are you sure that none of the wastewater has been draining through the pipe? If it hasn't it would be unusual that you haven't had odour issues and/or sewage backing up into the property through the lowest points (usually downstairs toilet / shower if you have one or the washing machine and kitchen sink).

Firstly you need to determine if it's your responsibility to fix. If it only serves your house then it's yours to repair but if it serves more than one property it's the responsibility of the water company. That are rules about building over sewers because of this issue!
Digging up the extension floor would be a last resort, they might be able to reline the existing pipe or tunnel under.
Have you got CCTV footage from the survey?

Thanks so much. I got another drain survey and it looks like there’s actually a second main line pipe, which our waste is draining into, but isn’t accessible from the manhole cover. So not collapsed!! Thank you for responding on this x

Collapsed pipes can often be patch lined, which means minimal digging.