Large crack on external wall

[jnix2]

Hi all

I'd appreciate your advice on this - i have zero buildng experience...but will try to include as much relevant detail as possible

There's a crack on the external wall which has been growing over the last couple of years - it goes right through and is visible on the front of the house.
The walls are plaster on top of brick, rendered on the exterior. There was lining paper on top, partly removed in the photo.
House is 1920's ex local authority - built on North London clay. The wall in question is south facing.

There are no large trees in the front garden - but some 1m high shrubs. There are trees in the street but the nearest is on the other side of the road, maybe 15m away.

We had an extension in 2005 - not adjoining the wall with the crack but obviously there was some demoilishing of walls going on in the rest of the house (in case that could've caused things?)

This is the crack - running from the bottom of upvc windows (installed 6 months or so ago) to the edge of an airbrick:

Close up of the window end - smaller crack running round the sill:

External view:

How worried should I be? What should I do about it?

Thanks in advance
Jon

 

[^woody^]

If it's ongoing, internal and external, then it's foundation movement if ground floor, foundation or lintel movement if first floor.

Trees, shrubs or leaking drains will be the most likely cause. You need to deal with the cause, wait for the ground to stabilise (which may include the crack closing back up) and then do the repair.

Instruct a local structural engineer to report on the cause. This might be cheaper than going through your insurance. If the cause is trees shrubs or drain leaks from other's land, then you (or your insurer) can claim off them at no cost to you.

 

[Deleted 224857]

Can you post pics of front of house. My uncle had sililar problem and it was due to bay coming loose

 

[jnix2]

Thanks both - missed out the important detail that it's downstairs, ground floor. House is flat fronted, no bays.

I'll get in touch with a surveyor

 

[^woody^]

I'll get in touch with a surveyor

Only if he is able to comment on ground conditions and building movement. If he can't, then use a structural engineer - else you may find that a surveyor does you a nice report which recommends another report from a structural engineer

 

[HERTS P&D]

Any drains or down pipes near by??

Andy

 

[tony1851]

@op; close up pics of a crack are rarely helpful - a few pics from further back showing context would be better.

 

[jnix2]

Thanks again everyone.

Yes, sorry, I think I mean structural engineer but I get them muddled up with surveyors. Point taken thanks.

There is a downpipe right next to the crack, which goes into a drain (rather than straight onto the ground).

In this pic, crack is below right of the window, behind the bush.

That bare brick wall (between us and next door) doesn't adjoin the house - there's a raised concrete drain surround in the way.

 

[Nige F]

I think Andy is on the money here - very likely the drain is broken underground Don't worry too much- dig and have a look.