You want to get yourself some decent PVA. We recommend the Unibond products – their mix is thick and acts as a great sealer for plaster. Some companies PVA's are weak, thin and very poor in quality so get a decent one. We need to mix the PVA with water because it's far too thick to apply as a stand-alone material.

Should you use PVA before plastering?

Secondly, in all cases, a three parts to one mixture of PVA and water must be applied immediately prior to plastering and it is essential that the plaster is applied while this coating is still wet. This helps bond the plaster to the surface.

Can you use craft PVA for plastering?

The correct mix for pva for plastering is 1 part pva to 5 parts water, and really only used to stop the plaster drying too quickly, plastering over silk paint with or without pva can only be as adhering as the paint before, pva doesnt make the plaster stick to the behind of a painted surface!