Crack in wall - time to worry?

[F]

We're about to have a window replaced by patio doors in a single story extension so I took the opportunity to investigate some cracking to the side of the window.

The crack has horizontal and vertical components and has been there a couple(?) of years. It became obvious when the wallpaper started to part. There is also a slight (~1mm?) step back in the wall surface below and to the left of the horizontal and vertical cracks that is worse at the vertical crack and fades to nothing as you move across the wall to where the horizontal crack runs out.

The horizontal crack runs along a mortar bed and the vertical one runs through three joints between blocks (top, middle and bottom courses in the first image) and through the two blocks between them.

Images at

able to tell me how serious or otherwise the crack is and any ideas on what needs to be done?

If it's of any consequence, I do know that the wall plate on which the roof joists rest is on the outer leaf of the wall.

TIA

[sm_jamieson]

Is the crack on the outside leaf at all, i.e. can you see it from the outside ? A photo of the outside may be useful. Cheers, Simon.

[F]

I can't see the 'same' crack on the outside leaf. There are a few bricks with vertical cracks, a few cracks along mortar beds and a few that involve both a brick and mortar, but nothing to match with inside.

I've uploaded a couple of images to

to show some of the typical cracks.

[Paul Andrews]

Frak, admit it. You know you're going to have to call in a structural engineer or surveyor. As a complete layman, that doesn't look good.

Paul

[Fred]

Make sure you're insured first!

[John]

He says it's in an extension, and also that the crack's been there a couple of years ... isn't it really just settlement?

John

(owner of a 2-floor extension, with cracks).

[Huge]

As someone who has had two lots of remedial work on their house due to movement in the last 10 years, I'd consider *very* carefully before calling in the insurers. Consider the following, from my experience;

- You will never be able to change buildings or contents insurers easily again. The first question they ask is "have you had a subsidence claim" and if the answer is "yes", their answer is "no"!

- There will be issues when you come to sell. I haven't reached this point yet, but believe me, there will be.

- You will have to fight, scream and threaten legal action to get the remedial work done to an acceptable standard. I ended up getting GBP7K worth of remedial work done to the remedial work...

- I could have done what the builders did, quicker, easier and cheaper(*). If the house isn't actually falling down, do it yourself. Get a surveyor to come and look, and if he says the cracks are cosmetic (and unless you can get a little finger into them, they likely are) then *don't* tell your insurers and fix them yourself.

(* Oh, I forgot. And better, too. The standard of workmanship once the insurers had subbed out the work three layers down was *atrocious*.)

[Andy Hall]

... and what is concerning is that this is advice from a very sensible person who, like myself, won't put up with bollocks from insurance companies, "the professions" and others who would seek to walk away from their responsibilities.

Very clearly it should be heeded.

[Steve Firth]

Not on the subject of movement, but on the subject of insurer subbing out work.

A few years ago a storm tore off tiles from the gable end of the house, making "quite a big" hole. The insurers, who were happy to charge inflated premiums for a listed building, undertook the repairs rather than allowing me to get in the local builder who does a good job, and has a yard full of matching clay tiles. Their builder put up non-matching tiles and didn't even randomise them, so we have a huge, obvious diagonal patch of the incorrect colour. LBO initially raised shit, we asked her to contact the insurers because I was exhausted with arguing with them. She gave up as well, so they can stay there until they change colour. ICBA to spend a thousand or so changing them.

[Ron Lowe]

I'd want to put crack monitors along the cracks to determine if there's still momement over a period of some months.

This kind of think:

's one of the first things a surveyor would do anyway.

If there is still movement occouring, I'd be wanting proffesional advice. If it seems stable, I'd probably make good and hope for the best.

[F]

As a layman, it doesn't, but that's why I'm asking for the views of those more knowledgeable/experienced.

Quite often, an apparently serious problem turns out to be merely cosmetic. I'm hoping that's the case here!

[F]

I had come to the same conclusion and won't be doing that for the very reasons you went on to quote.

[F]

Extension is 20+ years old and Management tells me that the crack has been there for much longer than two years. Doesn't time fly!

There's nothing to match on the outer leaf and, from memory, the foundations were at least two feet deep and had reached clay and rocks: the area is one in which glacial terminal moraine is found.

[dom]

I disagree. Unless the bricks/blocks are a significant way to pulling out of key (or if succesive courses have stepped out a significant portion of their width) - or it is a rapidly worsening situation - then nothing that bad is likely to happen in the short term. As a rule of thumb, I've heard if you can't get a finger in it, then it's not that serious. Your cracks seem much smaller.

First off, monitor whether it is a worsening or static situation. You can do this by putting masonry nails in either side of the crack and carefuly measuring between them once a month say.

If it's static, I would have no qualms about plastering over.

If the movement is continuing then you need to find the cause - possibilities include settling, subsidence, inadequate foundations, leaking drains, gutters or water pipes, tree roots, ground movement cause by drought - or at the very serious but unlikely end - old mineworkings!

Given that you said it was an extension, is it possible that this has a differential movement compared with the main building?

[Huge]

Ah, yes. Tiles. A few years ago, a storm tore off tiles from the gable end of the house, making "quite a big" hole. The insurers, who were happy to collect the premiums, undertook the repairs rather than allowing me to get in the local builder who does a good job. After a couple of weeks of water coming in, a couple of thugs turned up and slapped some new tiles on, got my wife to sign something and f*cked off. What she didn't notice was that they'd broken some guttering at the same time and bodged up a repair in the hope we wouldn't notice. Since it leaked quite badly and in an obvious place, it was a misplaced hope.

I ended up mending it myself.

[Weatherlawyer]

There isn't enough information. Just seeing the damage isn't enough without seeing what is damaged. Try again.

It is the type of damage you see when to walls fall apart. They are not keyed in by the look of it but why it has gone horizontally is not possible to guess with what you have shown.

[F]

I'm not sure what you mean by 'try again'.

As in the two leafs moving away from each other?

Sorry, but I don't understand what you mean by 'keyed in'. Lack of wall ties, poor bonding?

[Steve Firth]

There ought to be some law permitting one to take a gun loaded for bear and go hunting in the offices of insurers. I bet they have a law like that in Montana already.

[The Natural Philosopher]

Indeed. I regard insurance as essentially there to cover total loss from fire and flood, and theft.

Go for a BIG excess and fix the trivial stuff yourself - yeah even unto

15 grands worth of underpinning. Regard the interest on the excess mortgage you need to cover it as another way of paying 'insurance'.

What people don;t realise is that claiming small stuff 'on the insurance' simply leads to higher premiums. AND the bureaucracy involved means its always more expensive to deal through the insurance company than do it direct.

In short only insure what you cannot afford to pay for yourself.

In this case get some structural engineers in, and chances are they will tell you that you need to cut a tree down and possibly underpin a few meters of foundation.

[The Natural Philosopher]

Or heave :-)

Anything except 'subsidence' m'lud.