Cracks in breeze blocks in loft

[fouxdafafa]

Been in the loft today and noticed on one gable end a long crack in the breeze block inner skin. The crack goes through the middle of some blocks, not just down a joint. On one side of the crack I can move the blocks (about 3 or 4 courses worth) just by pressing with my finger. I don't think there's a corresponding crack in the outer brickwork. Is this something worth worrying about, and/or do something about? And if so, what can be done? House is about 25 years old and the ground in our area is clay-ish, so I imagine it's due to settlement. I have no idea when it happened - could have been there many years.

 

[dontbelieveawordofit]

are these concrete blocks or thermals?

 

[fouxdafafa]

are these concrete blocks or thermals?

That's a good question - I don't know. Is there a way to tell the difference?

 

[^woody^]

so I imagine it's due to settlement

In which case you have cracks on the inside and outside walls going down to the ground.

Just close the loft hatch and forget it, its a thermal crack not a problem.

 

[fouxdafafa]

In which case you have cracks on the inside and outside walls going down to the ground.

Just close the loft hatch and forget it, its a thermal crack not a problem.

I was guessing it was settlement. When it's safe to go outside without getting blown away I'll go and check whether there's a crack in the external brickwork.

 

[tony1851]

If it's lightweight block, it has a tendency to shrink soon after construction, causing vertical cracking; completely normal.

 

[fouxdafafa]

If it's lightweight block, it has a tendency to shrink soon after construction, causing vertical cracking; completely normal.

What's bothering more than anything is that I can move a whole section of the wall just by pressing with my finger.

 

[^woody^]

That's easily remedied then .....

 

[fouxdafafa]

That's easily remedied then .....

Push it over? Or fix it in some way? Is there something I can squirt in along the length of the crack? I was wondering about Soudal expanding foam - coz I have half of one left over from another job.

 

[^woody^]

One remedy is don't press it with your finger.

Another more involved remedy would be to get some 5x25x1000mm galvanised restraint straps and fix two across the vertical crack and (if possible) fit two across the bed joint that has cracked, and then leave it. Its probably been like it for years.

 

[fouxdafafa]

One remedy is don't press it with your finger.

Another more involved remedy would be to get some 5x25x1000mm galvanised restraint straps and fix two across the vertical crack and (if possible) fit two across the bed joint that has cracked, and then leave it. Its probably been like it for years.

OK, ta. I'll have a look at the second option - and maybe resort to the first. You're probably right that it's been there for years, and I'd be none the wiser if I hadn't gone up the loft today to find out what was banging in the wind, leaned on the wall and it moved!

 

[Nige F]

Was it the wall banging ?

 

[fouxdafafa]

Was it the wall banging ?

It's possible, I suppose. Never thought of that.