Could this be subsidence?

[housebuyingistheworst]

I had a full building survey done on a property and it indicated signs of structural movement. This refers to one horizontal crack in the foundations (photos attached). However, the surveyor refuses to say if it's subsidence ('it could be'). A structural engineer would say something similar without digging up the foundations. To make matters worse, there's a giant buddleia plant right in front of this crack, which could be the culprit.

Those who have experienced cracks /subsidence/ buddleias - what do you think? There are no internal cracks in the house or other signs of subsidence, but I'm worried. Would you go ahead with the purchase given this uncertainty? Your views would be much appreciated as I'm at a loss

Difficult to say from those photos but it does look more than normal settling of a building. That said subsidence isn't the end of a building , it should be straight forwardish to sort. It depends if you want to go through the mess of having it sorted and getting a discount of the house that's right. If it was my dream house then I'd get a SE report if not then I'd walk away.

@Chickencellar, thank you. I've contacted a few engineers. The problem is their reports would be just as inconclusive as the building survey. One said he would need to watch the crack over the course of one year (!) to be sure, another said he would need to dig around the foundations to see is there is any further damage. There are no other visible signs of subsidence, so this could only be cracked render. The house was built in 1930s and has been quite neglected over the past few years.

I'd want to dig down and see what it's like but I would think it very unlikely the owner will let you do that.

Even if it were just the render I'd still want to know why it's cracked.

Some of the possible causes are: the huge buddleia growing right next to the affected wall, damp in the porch area (also close to the crack) or old age of the property. Otherwise it's the start of subsidence as it's in London so it's built on clay soil.

I've got one more question. Even if I assume it's just a crack in the render, would insurers provide cover when I declare unspecified 'structural movement'?

It looks like it may be the render that's cracked, especially if there's no movement in the house too. I'm not an expert though. We've had a lot of old houses and have had subsidence in one but it was obvious the whole area at the front of the house had dropped inside and out.

If you have doubts though either step away or if you're desperate for the house you could request an indemnity insurance from the seller which would cover any costs associated if it is subsidence and needs correcting. Just be warned that this may invalidate any house insurance if you don't tell them that it's a possibility that came up on the survey, and it will increase premiums and the excess is usually about £1000 after work has been done for anything that arrises from it. It cost our seller about £25000 to put the subsidence right but that was a big bay window on a 3 storey Victorian property.

I'll need to call insurance companies and see how they approach the issue. If this was a case of confirmed subsidence, I'd have walked away by now. If they refuse to insure the house, I'll also need to walk away.

It does look like a crack I have which IS due to subsidence.
We were only able to diagnose subsidence by digging down and taking soil samples - they were wet with dirty water that had come from a drain. (Drain has now been relined / replaced).
Is there any evidence of this crack on the inside of the house too (or any trace of repairs made) ?

I suggest that you ask on this forum OP:
forums.moneysavingexpert.com/forumdisplay.php?f=16
There's an awful lot of knowledgable people on there.

We noticed a crack running along the gable end of our house when we had a second viewing. We arranged for an engineer to visit and do an assessment, and he said it was likely to be subsidence caused by roots of a pine tree too close to the house. However he said he wouldn't be able to confirm without digging a trial pit.
The engineer estimated it would cost us £10,000. The vendor didn't want to have a trial pit dug so agreed to have that taken off the sale price.

Once the sale was completed, we arranged for a builder to dig a trial pit which the engineer assessed. He concluded it wasn't a serious, continuous subsidence so we only needed the corner of our house underpinned (which coated £5,000. They then put ties on the wall in a few places and have monitored them over the last year. There hasn't been any further movement, so the engineer is going to sign off the issue as fixed.

When we bought the house, the internal walls were all covered in woodchip paper, but once we took it off we could see huge cracks throughout the house, in the corner of walls and above doorframes and windows.

Thank you! I'll ask on MSE and I'll call the insurers. Is anyone on here well versed in house insurance? If there's just one crack visible only from the outside (there's wallpaper indoors), could this alone make the house impossible to insure? There's absolutely no info from the seller as the house has been empty for a while and the person who used to live there is dead.

I'm a property loss adjuster. If it's subsidence and discovered within the first year it would revert back to the previous insurers.

If you go ahead with the purchase get rid of the tree which is close to the property.

After last summer there are many properties which are being affected.

If the property is old the walls may not have been properly tied in with shallow footing leading to lateral movement which wouldn't be covered by your insurance

In a geotechnical engineer (that’s a specialist branch of civil engineer to do with building/ground interaction and earth structures). I agree that you can only be sure by digging a trial pit and taking samples. In my experience subsidence cracks are usually vertical, or have the larger cracks running vertical - but that is just my experience based largely in Yorkshire, where the clay is much stiffer than London Clay and subsidence is often due to mining. With a budellia bush though, it’s unlikely to be big enough for the roots per se to be the problem. After last summer (2018), the water demand of the bush could have outstripped the moisture content of the clay soil and caused heave though, which could be what you are seeing here.

@BikeRunSki @Clarinet53, thank you both! This is very useful. Today I've talked to a big well-known insurer and they refused cover. Has anyone heard of an insurer that will provide cover despite the 'sign of structural movement' mentioned in the survey? Or is this really a lost cause?

I don’t work fir an organisation that does insurance work anymore, but it was Royal London who used to use the company I did work for. That was 15 years ago though.

Try NFUMutual or legal and general

@Clarinet53, ok, thank you. I'll speak to them tomorrow.

Often with subsidence you get cracks on the inside as well as the outside due to the movement. Have a word with a local surveyor company to see if they deal with a lot of subsidence in the area.
On an insurance perspective they are likely to put terms on a policy if there is suspected subsidence and may exclude existing damage etc.
If you have budliea it can cause massive cracks as it penetrates concrete badly if damage is caused by that you will find that isn't insured as its gradual and pre policy term
(I worked for an insurance claims dept for 5 years)

@Juliephine @Juliephine there don't seem to be any cracks inside, but there are wallpapers everywhere. It probably isn't subsidence but just the mention of structural movement (ie one external crack) seems enough to make insurers run.

The reason insurance companies are wary is subsidence claims often start at the 25k mark.
The other thing is if you have cracks like this have the plants also penetrated the drains , you can also run the risk of needing new damp courses etc which could cost you £1000s
Unless you get a more definative answer from a surveyor I would be wary of purchase there maybe a reason theres rather a lot of wallpaper.
Did your surveyor do a damp meter test inside ?
Also if you want to go ahead with purchase consider where the crack is ... Esp if it is on a load baring wall. It does look more than just rendering by that photo because rendering often subsequently falls off around cracks esp if you tap round it.
Also rendering cracks are superficial and then they fall apart.
I am no expert and only did minimum training on subsience due to the value of claims we appointed loss adjusters

I'd walk away OP. I lived though a subsidence claim on my last house which took six years to resolve (lots of monitoring and tree removal).

It really does become an obsession and the cracks I had were nowhere near as bad. You will not be able to get insurance to cover your house from your purchase where there is pre-existing subsidence unless the current insurer agrees to carry on. I'd go back to the sellers (presumably the executors) and ask who insures it now then start a dialogue with them.

Bear in mind though that it is quite likely the crack has not been reported to them so they may dispute liability.

TBH I'd say it was buying trouble..

I've already spent lots of money on the full building survey and legal fees, so I'm still hoping to find a solution. If I hadn't, I'd happily walk away. It's a good house (but not a 'dream' house, as these seem impossible to come by).

Update: I'm waiting for a callback from the insurance company currently covering the house. Are they obliged to keep insuring this property when the owner changes even when they find out about the crack?

Please walk away from this house. The losses you have made will be nothing compared to the upheaval and stress of trying to sort out a subsidence claim. Plus more expense. Insurers are experts at getting out of any responsibility.

Also, people are very wary of buying previously underpinned houses so you might not be able to sell it on. If you are insistent on buying it then I'd ask for a 30% reduction.