crack in wall outside and inside - advice?

wallofbeans

Hi All,

We noticed a crack on the back section of the outside of our house last summer. I assume it appeared during the heat wave, there were other cracks inside, in the same part of the rear of the house.

We did nothing about it except I filled in the interior cracks and put it on a list of things to do.

This week, over the last two days, I noticed one of the interior cracks that I filled in has reappeared. I checked others and most have come back.

This has brought the issue to the top of the list. But I don't know what kind of expertise I need to figure out exactly what is going on here and what to do to fix it.


Any advice welcome!

Doozergirl

That's significant enough to warrant a chat with a structural engineer.

Cracks tend to point to the source of the issue, except you haven't shown us the full walls and the ground and items around them. Context is the most important thing.

Wider photos would be more helpful to look for potential culprits .

Are you near London? That appears to be a London stock brick.

JimmyChanga

Looks like subsidence. How long have you had the house? Any works been done near it recently?

Doozergirl

So there are no trees nearby?

What is at the bottom of the crack? Any drains near to it?

Doozergirl

wallofbeans wrote: »

Added another wider pic if that helps...

I'd say it does.

It's pointing straight to the drain.

Victorian house, probably deteriorating Victorian drain pipes, likely built on London clay, you've the perfect storm.

I'd get a CCTV of your drains, but you're going to need a structural engineer, without a doubt.

Doozergirl

wallofbeans wrote: »

Had the house since 1998. Yes, big building work going on directly behind, council building new housing. Although, I think the crack was there before they started... not sure though..

It feels like it's extreme heat related is seems to reappear when it's very hot. Is that a thing?

Yes, a long, hot summer will cause the ground to shrink and that can cause subsidence in itself, but the proximity of that rainwater pipe is too interesting. You can't even see the ground there because of the decking.

Last year was long, dry and hot and could well have caused issues for people, but this year has not been. There's possible movement from wet ground due to a leak, but then if there was no rain for an extended period, the ground will shrink too. Both cause issues.

EDIT. Oh. And the tree. The roots can break drain pipes and the roots will also love a free water source.

I think a CCTV of your drains is in order. And check the sink is draining correctly. I can't see where it terminates.

It's up to you whether you involve your insurers at this point but it looks like a claim to me

JimmyChanga

Or foundation on what I presume is an extension added some decades ago has slumped. Trees can also suck the ground dry.

Doozergirl

We replied at the same time.

I'll let the structural engineer advise the course to be taken, but there is some inevitable disruption. I mentioned insurers.

That looks like it's been going for a while, in honesty, and it also looks like the previous ugly repointing (over the bricks themselves in places) on the wall near the roof was potentially hiding something.

Doozergirl

wallofbeans wrote: »

Updated with another pic of drain. It's about two feet from the bottom of the crack that sits at the top of the air brick.

https://imgur.com/a/0Y2uQfq

Both drain pipes going into this drain are plastic, the only original Victorian ones are on the back of the house.

It's the underground pipes that I was suggesting would be affected. Probably connected to the original clay that came from the cast pipe at the back of the house.

The way that shoe points towards the house and not exactly into the gully is a real concern though. It's not taking a direct route and if the gully is blocked then even more water will pour everywhere and seek the easiest route into the ground. Is that the RWP or the sink ending like that?

These things are often just caused by poor maintenance. It's so important to understand and keep an eye on where your waste water goes.

You've got decking there too, so if the area underneath it is flooding, you won't see it. I'd remove it as a priority as it's also close to what would be your damp proof course.

Any signs of damp inside?

JimmyChanga

Any ideas on what sort of work might need doing here? I'm freaking out a little about disruption and possible cost. Can buildings insurance cover this?

Call them up and see what they say. They will sometimes send someone down who will then check over months whether the cracks get any bigger.

It happens a lot so I wouldn't worry too much. Loads of scare stories on the internet.

Doozergirl

wallofbeans wrote: »

The extension may have originally been an outside toilet that was then connected to the house but I might be wrong. I assume built and then connected a long time ago though, as all the almost identical houses in this estate (all built around 1873) have the same extension section so perhaps they were all done at the same time...

The brickwork looks like it's all of the same age and closet wing extensions are very commonly original. I think the whole wing is of the same age, even if it's younger than the house.

Differential settlement isn't going to occur a century after being built.