Plaster under windows and problems

[RadarBailey]

I’ve just had some new windows put in and the plaster and render under them has come away (crumbled) the wooden laths are now showing. What do I need to do, clear out all the crumbled plaster and fit plaster board and re plaster, or do I re render and re plaster if that makes any sense.

Thanks

 

[trowelmonkey1]

well without seeing it it's hard to say and i'm sure you'll get some different advice on this but personally i'd clear the render/plaster from the laths, PVA the laths, use bonding to re-plaster flush with the existing wall level making sure you push enough of it through the back of the laths, when it's set to a cheesy consistency, cut it back 2-3mm to allow for finish plaster or easifill depending on your ability.

you may need to PVA the bonding once it's set but depends on when you're going to apply the finish and if you're skimming or not.

see what the other guys say too though, i know this type of repair can divide opinion.

 

[1john]

What type of cheese are we talking about here trowelmonkey?

 

[RadarBailey]

What type of render should I use. The stuff there now has hair in it and small pebbles. what do I need to mix?

Thanks

 

[NickB_99]

What type of render should I use. The stuff there now has hair in it and small pebbles. what do I need to mix?

Thanks

I'd go with Bonding (as trowelmonkey suggested above) for the undercoat.
The horse hair etc is in plasters from older days and wouldn't think it necessary to replace like for like.
Bonding would be easier to work with than Render I would imagine, when pushing into laths. (think this is called forming Nibs).
If you wanted to be sure, after the Bonding is patched up, cover the joins of old/new with scrim tape and skim over the whole wall.
Alternatively, if not experienced you may be ok with patches of skim feathered away from the windows where it's come away...or even skim patched with use of easi-fill for a sandable solution.

 

[Micilin]

What type of cheese are we talking about here trowelmonkey?

Please don't gouda.

 

[JohnD]

from your description I am guessing they are 100 years old or so, and the old laths are very likely to be rotten, and the nails holding them rusty, so I would be thinking about pulling off the laths and any old wooden grounds, fixing EML or plasterboard and plastering to that.

 

[joe-90]

John D's the Daddy.