Subsidence - advice please

[SharpBluePoster]

About to put my house on the market as am divorcing my husband. However it’s on clay soil and in the last couple of weeks a large crack about an inch wide has appeared in the corner where the ground floor extension meets the original house. Subsidence I assume, due to the weather drying out the soil.

The original house is 600 years old and wonky as anything. This is the only crack I can see.

I am terrified I therefore will never be able to sell it and be stuck here forever!

Looking for advice on what I should do as next steps.

You have to advise your insurer so that they can arrange a survey to confirm subsidence.

If the insurers confirm subsidence and it is underpinned then it will be sellable. A lot of homes on clay are going to be suffering in the drought.

I would fill it in, paint over it and not mention it.

I'd do this for now and given your circumstances OP.
With the very hot weather all sorts of properties will be experiencing similar issues.

I was going to do this but the crack is huge. Here is a photo, what do you think??

Do you think that’s possible with a crack this size?

It may well close up again when the rain comes. It's the differential foundations between the extension and the original house one or the other has much better foundations. Was the extension actually linked into the original house? You really need a survey to decide which bit is moving and decide what to do.

But you could just replaster into the crack and repaint, or wait until spring and see if it closes a lot and then fill and repaint.

You could get a structural surveyor to come and have look. I got a survey done in my wonky Edwardian house before putting it on the market. I was reassured that it was only differential settlement due to different foundation depths under different parts of the house, and that an insurance company wouldn’t be interested. This was a very reputable structural engineer who used to work for insurance companies. Cost me about £500.

Thank you. One has been recommended to me so I have asked him to come round.

No, the extension isn’t linked to the original house. It’s just a single storey bathroom that’s been added on. Original house looks completely fine.
I need to get it on the market ASAP so will look into getting it plastered and decorated.

Industrial quantities of polyfilla, the patience to build it up in layers and a good sander is what you need.

ETA: I'm sure the sales of polyfilla plummeted after I moved out of my old house.

If you get a surveyor around then you'll have to declare what they say to the purchaser.
So your options are contact your insurer and ask them for advice or fill and paint.

Lots of filler and paint. Think I did the cracks in my old house 4 times whilst it was on the market. Surveyors can also book in with very little warning, so once you’ve got the offer still keep on top of the basard

If insurers are involved they’ll want to monitor it before they do anything, from experience that could well take a year especially as once it gets wetter it’ll probably move back. Personally I’d get it filled and sell quickly.

From my experience, if it is differential settlement, and it sounds like it is, then insurers are not going to be interested.

I didn’t declare anything to any prospective purchasers - I thought they might ask because of the clearly wonky internal door lintels, but none of them did, and the surveyor didn’t advise me to let my insurers know or anything, in fact he was the one who said they wouldn’t be interested. I did let the eventual buyers know but only in a ‘btw, the house isn’t falling down but you’re going to have to get handy with the polyfilla every so often’ ’ type of way. They never got a structural surveyor in prior to purchase.

Well that's fine in the event that nothing is found but there would be questions on the form asking. And if OP does have some issues then she'd have to declare it as she then officially knows. So if she's wanting to not officially know, polyfilla is her best option.

I can't remember exactly, but I don't recall questions asking if I had ever suspected there was subsidence or had a structural survey done. I don't think it is like neighbour disputes, planning permission or building regs where you have to declare them.

It's a standard question on the TA6 form

You cannot cover up a 1 inch crack! Any competent surveyor will see this. This is differential settlement - the foundations for the old house (if they exist) are not the same as those of the new extension. The extension should have been designed for differential settlement. It’s difficult to say if this is truly subsidence. However I’d deal with it via your insurance or get your own survey from a structural engineer so you know what this is and possible remedies! And costs. It might not drag on too long but this crack won’t close much now it’s happened.

That's not 1" is it? I hhad similar cracks and told insurance and they told me to fill them in.

Very old buildings do have a habit of moving about. If it has been caused by the prolonged drought, which in all likelihood it has, then once we've had some serious rain it should start to close up again. Maybe delay putting the house on the market for a few weeks and see what happens?

Why are people saying ‘fill it in and ignore’, as if potential buyers for a more-than-half-a-millennium-old building aren’t going to get a L3 survey?

If the purchaser commissions a survey then they will declare it directly to the purchaser. If they do this, prepare to take a big hit on the price.

Don't just fill it before getting a specialist look at it. Hidden subsidence will eventually show up.