Could cracks in the breeze block inner wall be a problem

callmechar

I'm decorating my daughters room. I've noticed on the outer wall there was a crack from under the window to the party wall. It went down about 6 inches from the window edge then runs straight across the wall. There was also a thinner crack above it. Both cracks are above and below a row of breeze blocks which are on the inner wall, which is plastered over. Looks to me like the mortar around the bricks has gone. This must have happened in the last 2 years. It rippled the wallpaper. We decorated this room 2 years ago.

I'm an end of terrace. House built in 60s.

There is also a crack running the edge of the party wall and the adjoining wall, where the 2 walls meet. In the corner of the room. We've had this in a couple of rooms.

There don't appear to be any cracks outside. Just one or two but they've been there ages.

Could this be something to worry about or does this sound just like the mortar needs replacing in those areas due to age? Seems to be mortar issues in both areas.

Thanks

callmechar

Here's a photo. I've raked out the crack a bit

Furts

This looks like the outline of a block that is forming part of your wall. This is an area that is subject to shear/loading, and it could be the mortar is weak, or there may be little, or no, mortar there.

My suggestion is to rake it out to inspect. Whilst not a text book cure, I would be suggesting around 50mm depth of traditional (not water based) Gripfill put into the joint to glue it together. Then fill over this. The Gripfill will take a while to go hard - some days in fact. An alternative is expanding foam, but you would ideally need a gun to control the foam.

If it were my home I would not be worrying about it once it has been filled in. That is assuming there are no cracks elsewhere, or signs of settlement, or any trees nearby.

callmechar

Thanks is that the general consensus?

tony6403

My two-penneth.
It could be that the cracks have been caused by the base coat plaster being applied too thinly (fyi a base coat is usually 10mm to 15mm thick) .
I would hack off a very small area of plaster where it is cracked to reveal its thickness and to check the condition of the bed joint of the (assumed) block affected.
I will be very surprised if there is not a standard 10mm bed joint .
Please let us know what you find if you do investigate.

cyclonebri1

You need to determine if the movement is done.

Rake out and repoint outside

Chip of plaster , repoint inside and re-plaster or do as advised above.

Whatever, keep an eye on the suspect area in the immediate future.

We used to epoxy glue glass strips across suspected slumping areas in the factory I used to manage, a visual indicator of future movement to expand on what I've said.

Plus another vote for don't worry.