You show me a website that says don't use PVA because i can't find one, infact don't bother, continue in your little bubble world where everything...
Get off your band wagon and accept PVA does the job and like i said it's your poor skills if your work failed not the PVA which is being used for...
Are you joking
If you have ever had problems putting PVA on an external wall then i'd say the problem lies with you and not with the PVA
You either need to knock it all off and render the wall or render over the dash to get a smooth finish
Render with sand and cement or another...
have you tried a wire brush on a grinder? I don't think you will find any acids to remove the stain and get it to look uniform.
Aye what boxer said. leave the area until it's nearly gone off
Aye get out the elbow grease
You should never mix PVA with plaster
whoever did the plastering is not a plasterer
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