Cracks in solid walls?

[zx9]

Hi,

I am about to start renovation of a old (pre 1930's) victorian terrace and am not sure how to go about repairing the cracks in the walls. Mainly because i'm not 100% what they are made of, they feel & sound like solid brick. any help on what to fill the cracks with and prep for painting would be great. thanx. (ps-i will be restumping before i patch the walls)

[Tools]

If you are restumping under the wall then they are not brick. They will probably be lathe and plaster. Is it weatherboard on the outside?

Tools

[Dirty Doogie]

You really need to know what the wall material that has cracked actually is and if the cracks are structural cracks.

In some terraces they would lime plaster straight onto brickwork and finish with a caseain glue polish coat, or maybe it is cement render.

If you could post a pic it might be possible to determine the surface material and cuase by the pattern of the cracks. we also need to know how big, deep, wide the cracks are.

[rod@plasterbrok]

Usually you would have rendered walls here is how you fix them.

http://www.how2plaster.com/restlath.html

Cheers Rod

[zx9]

You really need to know what the wall material that has cracked actually is and if the cracks are structural cracks.

In some terraces they would lime plaster straight onto brickwork and finish with a caseain glue polish coat, or maybe it is cement render.

If you could post a pic it might be possible to determine the surface material and cuase by the pattern of the cracks. we also need to know how big, deep, wide the cracks are.

yep the place is brick, only one set of stumps though the middle, the bearers sit on the walls at each end, the walls are shared with neighbors, here's pics, thanx for the info

[zx9]

Usually you would have rendered walls here is how you fix them.

http://www.how2plaster.com/restlath.html

Cheers Rod



thanx Rod, that link looks exactly like my cracks, looks pretty simple to fix

[zx9]

ok it looked easy enough so armed with the right tools following the advice i'd been begin i began by scaping the cracks back to the wall in order to fill. suddenly a large (bout 50cm x 20cm) peice of the plaster fell and i was now staring at the brickwork underneath. i left this and begin with the smaller cracks until i realised there was so many tiny cracks that the all the plaster on wall would probably fall off if i did all the cracks. so what to do now...

do i need to fix scrape & fill these tiny cracks, or will paint fill them. how do i fill these big holes that i've created. how do i fix the uneven ceiling? should i just call it quites and get a professional in ... what would that cost, who would i call?

i spoke to the restumping guy and it seems the cracks are from movement in the building due to age. (it's probably about 90 years old) he said the building may move further with time but you never know.

so any ideas on where to go from here?

[juan]

ZX9
For my 2 bobs worth(I am not a plasterer of builder) it looks like there is some serious movement there and some structural issues. I suspect unless you can solve the foundation issue then the cracks will be back pretty soon. If it were mine I would first determine the cause of the cracking and if it is all too hard to remedy then seriously consider plasterboarding over the top of the masonary wall.

Cheers

[rod@plasterbrok]

It is good that any loose drummy bits like that fall out. Although if there is too much falling out you may have to start fresh.

It really depends on how bad it ends up after digging out the cracks. Surface cracks or spider web cracks do not need to be raked out to the brick, just the major cracks. Or you will have no wall left :) With the spider cracks (named cause they look like a spider web) just rake out about a mm deep and set coat over the area.

Every job is unique and will require the judgement of an experienced person if you dont feel confident to call it right.

Cheer Rod

[Dirty Doogie]

It looks like your plaster is set onto cement render and I'm sure i can see cracks going through the render. In the second photo the plaster looks to have cracked along the wet joins in the render underneath (dodgy dodgy dodgy) which appears to been applied in stages. Getting plaster to stick to old cement or lime render is tricky especially if the wall is subject to movement.

When the piece of plaster fell off the wall - the render came off with it?? Were there any cracks in the bricks?

I would suggest you do all the structural work before you try repatching the plaster.

If any more chunks fall off I'd just hire a small demo hammer with chisel bit and completely take the render and plaster off. Might even be able to do it with a hammer and bolster. Then gyprock.

Also - in the second photo - are those marks on the lower part of the wall mould??

[zx9]

ZX9
For my 2 bobs worth(I am not a plasterer of builder) it looks like there is some serious movement there and some structural issues. I suspect unless you can solve the foundation issue then the cracks will be back pretty soon. If it were mine I would first determine the cause of the cracking and if it is all too hard to remedy then seriously consider plasterboarding over the top of the masonary wall.

Cheers

yep there is some serious movement, the restumper said it had moved over time, (90 years or so) quoted me 8k to have the wall underpinned to stop any more movement, but he also said given how much/or little it had moved in 90 years that it might not move any more or might move a little over 10 years or it could move tomorrow, up to me to take the chance, being somewhat optimistic and also on a tight budget i've got my fingers crossed for the 10 year scenario. so i am trying to repair the cracks now. <?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /><o:p></o:p>
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it's only one wall that has this movement.

[zx9]

When the piece of plaster fell off the wall - the render came off with it?? Were there any cracks in the bricks?

yep, as i mentioned in my last post, i'm told the wall has moved a little over the last 90 years but am taking the chance that hopefully it won;t move much further over the next 10 or so or whenever i can afford 8k to have the wall underpinned.



If any more chunks fall off I'd just hire a small demo hammer with chisel bit and completely take the render and plaster off. Might even be able to do it with a hammer and bolster. Then gyprock.

Also - in the second photo - are those marks on the lower part of the wall mould??

no can't remember seeing any mold. what would i attached the gyprock too?

[zx9]

thanx for the info so far guys, i was confidient when i started out but after having a large chunk of the render fall away it's starting to look like a much bigger job. good to know i dont need to scrape back all the hairline spider cracks. am also a bit worries about how to fix the sagging ceiling, it's only sagging in one corner.

thanx

Bernie