Cracks in brick wall where extension joins

[edthegr8]

Hi,

I have just been outside the house and noticed a vertical crack in the outer wall that is at the point where the original house wall (built 1980s) and the more recent extension.

The crack is vertical and goes through some bricks as per the photos. Is this caused by the extension settling and pulling away from the old house or is it likely to be a foundation issue.

The crack doesn't look new to me but was never mentioned in the full survey that we had done.

How bad does it look? Like I say, the crack is in the exact position where new meets old and does not extend beyond the height of the single storey extension

Untitled

• edthegr8
• 16 Apr 2012
• 1

Untitled

• edthegr8
• 16 Apr 2012
• 1

 

[^woody^]

It's normal. That cracked brick in the first photo, looks like it was cracked when the extension was first tied in

Just squirt a bit of clear silicone in for now and monitor it.

 

[edthegr8]

Thanks Woody, my concern was that the cracking extends vertically through the bricks and mortar up to just below the roof level of the single storey extension.

Would the bottom brick cracking when the extension was tied in have caused those above to crack?

It's been like that for about 17 years if that is the case as that is when the extension was built.

 

[^woody^]

The extension will move, some years more than others and this type of bonding will always tend to crack. A straight flexible joint is preferable to accommodate movement to extension additions, but its not important now

On this basis, whilst there has been movement causing cracking, it is nothing unusual, or unexpected

It would only be a concern if the cracks continued to widen, or got progressively wider at the top. 5mm wide or more

The bottom cracked brick would be irrelevant as it seems to have been done when built, but the other joint cracking is due to slight movement or shrinkage after construction.

It's not worth trying to repoint this as it will always form a hairline crack, and the repointing will stand out a mile. On the basis that this is not going to get much worse, its best to just fill the crack with some clear silicone, and this will be unobtrusive. Or if you like, just blow or flick some sand or some dust off the floor into the wet silicone to blend it in

Just look at it every six months from now for the next 2 years or so

 

[edthegr8]

thanks Woody, you've put my mind at rest a bit. I will keep an eye on as you advise. Hopefully they'll stay as they are.