Subsidence? House purchase nightmares - can you advise?

[DevonMaman]

So we have SSTC and this has been the case for some time. We have now identified what we hope is the property for us and had a level 3 structural survey done today by a RICS qualified surveyor.

They have identified some serious cracks which they think relate to a busted drain. When I asked whether this was subsidence he said we need to be very careful about using this word and suggested that this was not the case. I am not an expert, at all, but I am worried.

Would you get a structural engineer in to review the situation?

If it is confirmed as subsidence, will this mean we will be unable to proceed with a mortgage/buildings insurance irrespective of whether it is easy to fix? If there would be lending/insurance issues, would these be resolved if the issue was fixed prior to completion by the vendor?

Has anyone else been through similar?

This is the second potential purchase that we have had a disappointing survey with and I am tearing my hair out with worry.

This must be so fustrating for you. I guess there are a couple of issues and I’m not sure if I can help but I can describe what happened to me:

• you are in the middle of buying I guess with mortgage and insurance to get. I think, but I could be wrong, that they like things to be investigated subsidence wise which could delay both. Has the seller got insurance? This would be under their existing claim would it not as they still legally own the house?
• If it is the drain being cracked, once it is fixed then the subsidence is fixed. Cracks are defined in the BRE website and measured by the width. That one doesn’t look awful but it does look like subsidence because of the diagonal nature of the crack (not an engineer)

I only had internal cracks, but they were diagonal like that and there were a few of them in the end, but one main one the rest pretty superficial. Basically one corner of my house was sinking into the ground, because the drain had cracked underground - the drain by my front door - and the water seeping out had caused the ground to shift and lower the house.

So once the drain was fixed, no more water seeping out and no more cracks appeared.

I got the insurance involved and they put a camera down the drains and also tested the ground. It’s the only way to check, the structural engineer did not do this. The insurance paid out for the fixing of the drains and the cracks, and my insurance went up a bit. I sold the house and it was a bit of a pain as it was marked as ‘historical subsidence’ but it was unlikely to ever occur again, but I had to drop the price a bit and some buyers were put off. Just the word puts people off as they think it’s all ground heave and foundations, but most, like mine, are not.

I guess though, you are in a tricky position and I”m struggling to advise. Insurance may not want to insure you for subsidence, if there is an existing problem before you insure.

https://bregroup.com/insights/assessing-cracks-in-houses/

I have those cracks and it's not subsidence.

Can be settling, can be water - the surveyor should be able to say with reasonable certainty what the cause is.

@WhereIstand thank you! What is causing it with your house?

The surveyor has suggested it is due to the drain and water basically.

@DevonMaman This is quite difficult. They are cracks in the mortar but not the bricks. So it’s probably not serious. It depends on what the vendor is prepared to do on their insurance or pay for. They could start a claim and get the drains investigated. Or they could just pay for it. Selling a house with cracks is rarely a good idea. It’s best to find out what’s going on. If it’s fairly inexpensive to put right, you can possibly negotiate on cost. If they won’t investigate it’s an expense for you.

It doesn’t look bad enough for subsidence requiring underpinning but it needs investigation by a drainage camera.
The surveyor is probably right if no other cracks are evident.

The wall crack: Is that an extension? Maybe a slight settlement crack due to differential foundations and how the buildings move a bit over time. I would not worry too much.

It’s the size of the cracks and the amount, the gap measured in millimetres that is the severity - that’s what my structural engineer did that determines the action to rectify the cracks.

But the size of the cracks doesn’t tell you what the cause is, or whether they will get worse. That’s why sometimes they put markers on the wall and measure change over a year. But a camera down the drain will tell you if there is damage to the water pipe.

@TizerorFizz

Thank you so much for taking the time to reply. Essentially the vendor is an elderly lady who has moved out into a care home and her solicitor has POA. They have negotiated hard up to now on her behalf and are not willing to fund any investigations.

I’ve contacted a drainage engineer this afternoon to try and get this booked in, at the least.

I really hope we can figure it out so we can still move forward.

The wall crack is not an extension, though there is an extension much further down towards the right. I can post the floorplan if it helps to visualise?

Good luck with this, I guess if this was me I wouldn’t be massively over worried, but the only thing is insurance and whether it would cover it if it got worse, so best investigate. And then if you do go ahead, contact an insurer and make sure they wont’ be funny about this going forward?

Another possible cause for that main diagonal crack could be If the soil is clay based .the last few years of extreme heat and heavy rain have caused thermal movement in a lot of properties which can show like this .

Ours are just settlement cracks, although one crack (identical to your brickwork external step-down crack) is down to some crappy guttering - I wouldn't be too worried at all to be honest, our surveyor said to only really be concerned when the cracks match inside & out (basically daylight through it!)

Clay soil is another culprit, like the PP mentions; we're getting such extremes of weather (really hot, really wet) that I think it's going to become more common.

@WhereIstand your surveyor is funny! I had to repair cracks which were only internal and under 5mm in width and this was classed as subsidence. I think I want your surveyor 🤣

Are there any internal cracks? That would be a big red flag for me. (Veteran of subsidence.)

Funny?

Your surveyor must have had good reason/evidence to conclude your cracks were caused by subsidence and not settlement or another reason.

Hi DevonMAman,

we have a very similar situation (subsidence identified at survey, engineer thinks caused by drains, and drain survey showed lots of cracks and displaced joints). SE says Fix the drains and will solve the problem. Current owner hasn’t logged it with their insurers.

How did this end for you? Insurance etc?
thanks
J

Ask the vendor to get a cctv drain survey from a structural engineer. Once you had that report you can decide what to do.

So yes CCTV drain survey revealed cracks and fractured joints, confirming what the engineer suspected. Just wondering best way forwards with insurance etc

We had a problem when our rear extension was built. The builder spotted some movement in the bathroom corner which we couldn’t see as it was rendered, and he checked inside and there was a cracked bathroom tile in that area - behind the loo and I hadn’t noticed it. We got a structural engineer in who said it was almost certainly a drain problem as it turned out to be. When the old 60s extension was thrown up, the external drain was not filled in properly and it was giving way. It cost a little more on top of the extension cost, can’t remember how much exactly, to sort it out once the old extension was pulled down - but it was easily sorted. So if you want the house, it might well be worth sorting out rather than walking away.

Ask the vendor to get a drain survey. That will tell you lots.