Can this plaster be saved?

[Tom]

I've got some newish (2-3 years old) lime plaster that's become cracked and loose, due to excessive vibration on the outer wall. Is there any way I can 'save' it or does it need removing and replacing? The loose bit is from the crack towards the window. Thank you.

 

[stuart45]

It looks like it's blown and needs replacing. It probably sounds hollow when you tap it.

 

[Tom]

It looks like it's blown and needs replacing. It probably sounds hollow when you tap it.

Yes, it does sound hollow. I just wondered if it could be, I don't know, 'stuck' back on by, maybe, by injecting some lime/sand mix behind it. Would that not work? I think I know the answer :roll:

 

[Nigel Watts]

I would cut out the defective parts and replace. What is behind the plaster and how was the wall prepared?

 

[Tom]

I would cut out the defective parts and replace. What is behind the plaster and how was the wall prepared?

I think you're right, Nigel. I was just hoping for a quick fix. Once again, this house is making me work for the results :lol:

Behind the plaster is brick that was quite rough. I've no qualms with the way the plaster was applied, and I know that it's excessive vibration on the outside of the wall that's caused it to crack. It was caused when we were removing the front of a concrete sill that had been poured in situ and was made using the strongest mix possible :roll:

 

[Nigel Watts]

If you keep a tub of lime putty, some sand and some hair in stock I find making small repairs to lime plaster is not much trouble.

 

[Lime]

Most people use chisels or kango hammers to remove blocks of concrete on buildings but the vibrations cause much damage to the rest of the structure.
To cause plaster to fall off means the whole structure is damaged/weakened.
Old houses are quite easy to knock down but impossible to replace as they once were.
Always try to aim the blows in a downward direction so the force travels down through the wall.


However a much more sensible method to remove concrete/cement blocks (if space permits) is to use an angle grinder with diamond cutting blade.
The cuts don't have to go right through but will make the concrete weak and easier to break up.
Avoid heavy blows if at all possible.

 

[Tom]

Well, the plasterer is coming back soon to do some other bits and bobs, so I'll get him to do this while he was here. I just really want to start again in this room but if it's not such a big job then that's ok. Thanks, Nigel

 

[Moo]

Most people use chisels or kango hammers to remove blocks of concrete on buildings but the vibrations cause much damage to the rest of the structure.
To cause plaster to fall off means the whole structure is damaged/weakened.
Old houses are quite easy to knock down but impossible to replace as they once were.
Always try to aim the blows in a downward direction so the force travels down through the wall.


However a much more sensible method to remove concrete/cement blocks (if space permits) is to use an angle grinder with diamond cutting blade.
The cuts don't have to go right through but will make the concrete weak and easier to break up.
Avoid heavy blows if at all possible.

There should be a section on PPUK entitled "Essential Knowledge".

And that excellent piece of advice should be right at the top.

 

[Tom]

God, I can feel another slagging off moment coming on :roll:

Yes, we used a breaker because of the accessibility. The concrete was (is, as some is still in there) as hard as anything the builder has come across before. We very nearly gave up because it was so difficult to remove (hence why some is left inside the wall), coming off in very, very small pieces. It was one of the most frustrating jobs on this house! The pressure was downwards; it's a sill at the bottom of the window.

 

[Flyfisher]

We've discussed the use of 'repair washers' (or penny washers) for stabilising wayward plaster before, although I think it was mostly in the context of screwing lath-and-plaster back onto beams when the lath nails have rusted away. I wonder if such a thing would work in this situation?
http://www.screwfix.com/prods/40619/Bolts/Washers/Penny-Washers-A2-Stainless-Steel-M10-X-30-Pack-of-10

Having said that, it looks like a fairly small area so it might be just as easy to remove the blown section and replaster, especially if there is other plastering work to be done as well.

 

[Flyfisher]

Most people use chisels or kango hammers to remove blocks of concrete on buildings but the vibrations cause much damage to the rest of the structure.
To cause plaster to fall off means the whole structure is damaged/weakened.
Old houses are quite easy to knock down but impossible to replace as they once were.
Always try to aim the blows in a downward direction so the force travels down through the wall.

And on a similar theme, I found much the same thing when working on part of our roof, which had reed-and-lime 'sarking' under the tiles. Using a hammer and nails for the various repairs resulted in the lime being vibrated off the reed and would have caused almost as much damage as I was in the process of repairing. The answer in my case was to use screws thoughout and completely avoid any hammering. It cost me a small fortune in screws but saved a lot of damage, although if it wasn't for cordless screwdrivers, I'd probably still be working on the roof!

 

[Tom]

Hi FF. I think you're right about letting the plasterer redo it. Oh well, it's keeping him employed, I guess :lol:

Yes, thank goodness for cordless screwdrivers. I can't imagine doing your roof with a manual one. You'd end up screwing in yer sleep :shock:

Penners......sit down!!!!

 

[Moo]

God, I can feel another slagging off moment coming on :roll:

Oh, I wasn't being critical of you, DWB.
I just meant that it's a costly mistake that most of us could (and, in my case, would) make unless we had been forewarned.

 

[Tom]

God, I can feel another slagging off moment coming on :roll:

Oh, I wasn't being critical of you, DWB.
I just meant that it's a costly mistake that most of us could (and, in my case, would) make unless we had been forewarned.

Pheweeee! I could feel War and Peace starting all over again :lol:

 

[stuart45]

Using the kango to remove external render has been known to cause problems on cavity wall properties as well. The vibrations have sent pieces of brick and mortar snots down the inside of the wall and blocked the cavity causing dampness.

 

[MatthewC]

If you are intending to replace that plastic window soon (which you mentioned elsewhere I think), then I suggest you get that done first, or else you might have to do the plastering job twice.

 

[Tom]

Yes, Matthew, you may be right. I will be getting the windows done but I'd like to get the new stable block built first. Mind you, it's not that bad so I can live with it in the meantime. If I could have done a quick repair I would have but if it's got to be replaced, I'll wait. Thanks for your answer.