Cracks everywhere

[CrowdedBus]

I bought a 1930s detached house 18 months ago. The render had clearly been patched up in the past, mainly around the PVC windows installed 3 years ago (I.e 18 months before we bought), but there clearly had been other repairs, including a horizontal line right across the house. The brickwork below the bay window had also been repointed at some point in the past. Nevertheless, the surveyor thought it was all just historic and not a problem.

Now cracks have reappeared all over the house. The patched up render has cracked again and there are diagonal cracks coming from all the upstairs windows to the roof. Some go right through the wall and are visible inside. The bricks under the bay window have cracked again where they have been repointed. There are also cracks on both sides where the bay joins the house. All the cracks are hairline at the moment. I wouldn't be too concerned, but some of the cracks go through the wall and that has raised a few eyebrows.

We've had the trees in the garden checked and apparently they aren't a problem. We tried having the drains checked, and the bits the person could see were fine, but the manhole to access the drains has been buried under the kitchen floor, so not all could be inspected.

I've spoken to a structural engineer, but he wants to dig trial pits, which would involve digging up the patio and driveway. I'm reluctant to do this unless I have to, and the wife is adamant we don't pay for any advice as she thinks the cracks are just because the house is old.

I'm stuck what to do now and would be grateful for any advice. It doesn't seem like subsidence to me since the cracks are right across the house rather than being local to a subsiding area. Could the explanation simply be that the people that fitted the windows did a bad job, smashed the walls up a bit, didn't fit lintels and then did a bad patch up? I should also add that we have shallow foundations and live half a mile from a quarry which detonates explosives daily causing the house to shake. Some of the cracks also appeared after a small local earthquake earlier this year.

Thanks

CB

 

[stuart45]

You need to put some photos on.

 

[tony1851]

You need to put some photos on.

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• tony1851
• 28 Jul 2013
• 1

 

[tony1851]

You need to put some photos on.

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• tony1851
• 28 Jul 2013
• 1

 

[CrowdedBus]

Tony1851 - that's a fine drawing, but not wholly accurate.

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• CrowdedBus
• 29 Jul 2013
• 1

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• CrowdedBus
• 29 Jul 2013
• 1

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• CrowdedBus
• 29 Jul 2013
• 1

Here are three images. First one shows horizontal crack on front. Second shows typical crack from window. These are present on all upstairs windows, and all run from the middle of the side rather than the corner. The third shows the inside of that crack.

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• CrowdedBus
• 29 Jul 2013
• 1

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• CrowdedBus
• 29 Jul 2013
• 1

These two are of the bay window. The first is the brickwork on the ground floor and the second where the bay joins the house (sorry its the wrong way round). I think this problem is separate to the others, caused by either subsidence of the bay or faulty installation causing the bay to detach from the property.

Any help would be very much appreciated.

Thanks

 

[tony1851]

Quite often the bay pulls away from the main wall slightly because the foundations are usually not as substantial as the main house foundation.

The horizontal cracks above the front door suggest expansion of the bed joints in the brickwork. Is it a cavity wall? If so, the expansion could possibly be caused by corrosion of the wall ties. Less likely might be sulphate attack of the mortar, though this would have been caused by prolonged dampness, which would be unusual in that position.

There are a few experienced surveyors here - see if they come along in a while.
(No offence intended by the sketch!).

 

[^woody^]

It does seem that the render cracks are more to do with poor previous repair than anything

Once a building cracks there is always a weak point and rendering and plastering over cracks leaks to cracked render and plaster later

The horizontal render repair does seem similar to a previous brick stitching repair

The crack to the bay is a sign of movement which is common for this type of bay

I can't see what trial pits will achieve. The age of the property will be known and the foundation type can be determined from that. Likewise, ground condition can be determined and the cause of ground movement will be drain leaks, tree roots causing shrinkage or mines

The cracks are not bad enough to be major subsidence, and the best thing to do is monitor them yourself over at least 12 months, and then you will see if there is ongoing movement, or seasonal movement

You need to CCTV all the drains. Partial survey is as good as no survey

As for the trees, what do you mean that you have had them checked? Any tree or large shrub within 15m of a house can cause ground movement

 

[HERTS P&D]

What did your survey say when you bought the most expensive you will ever buy?

Andy

 

[CrowdedBus]

Woody and tony1851 - thanks for giving your view. Much appreciated.

An experienced local tree surgeon said the nearby trees are not a problem because of their distance from the house and local soil type. I'd like to check the drains but that means digging up the kitchen floor.

The surveyor said the cracking was historic and nothing to worry about. i'll get in touch with them.

Of all the research on this I've done, I can't find a cause for either such widespread damage, rather than localised damage around the problem or cracks from the centre of the window, rather than the corners.

 

[HERTS P&D]

Did you get a cctv of the drainage system? Did you watch a dvd?

Andy

 

[CrowdedBus]

Yes. Got a DVD and the bits they could see we're all fine.