PVA to stop the buggered plaster sucking the moisture out of the new plaster, causing it to crack like buggery.
You want it to dry equally, and slowly enough not to crack.
@Dammit started
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PVA to stop the buggered plaster sucking the moisture out of the new plaster, causing it to crack like buggery.
You want it to dry equally, and slowly enough not to crack.