Filling deep cavitys between render and wood?

15 May 2016
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United Kingdom
Hello all,

I've been taking off door architrave for stripping and noticed that chunks of the old sand mixture render between the wood frames and the black clinker brick wall cracked off and I pulled them out to reveal these deep cavities. Just wondering what is the best way to go about filling them in? I've got some bonding plaster, shall I just fill it will lots of that? Or should I fill it with loose plaster shrapnel then fill in with bonding? cheers


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Assuming no more plaster is blown then:
If you have any Pva handy then mix with water 50/50 and prep the openings.
If the sub-frame is secure then fill the gaps with lumps of semi-dry anything. Keep them 20mm shy of the wall surface.
Then use any backing plaster or render and a skim finish.
cheers vinn. How do you mean semi-dry anything? I got bits of old plaster shrapnel? Otherwise maybe I can mix a small bit of bonding, wait for it to dry a little and stuff that in.
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If it were me, I would fill the gap with bonding plaster then skim with whatever you have to hand ,multi finish or filler.
Although if you have any multi finish to hand , you can mix it 50/50 with bonding plaster and do it in one strike and smooth off with a wet knife or trowel. If this is done neatly you can paint over it when it's dry and it won't look any different to the surrounding area.

cheers Mike, I'm going to be using bonding on all the cracks so will fill then. I think it may be easier to just slap in the bonding like you said ;)

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