PVA Primer & Patching
May 14, 2011 10:40 AM Subscribe
Can I apply more joint compound over PVA primer?
I'm finishing drywall on a 16" vaulted ceiling with clerestory windows. I know for a fact that the drywall is not very flat or smooth, and have taken due care with feathering out the compound, but it's to the point where I need to start priming it in order to see where the deficiencies are.
I know that PVA primer is 'special' because it soaks into the joint compound to a greater or lesser extent, dries quickly and hardens the compound, and gives a decent surface for you to apply a thicker 'hide' primer to even out the differences in texture between paper and sanded compound before your finish coat.
However, it's likely that once the PVA primer is up, I'm going to see some shadows and lines that I didn't see before, and I'm going to want to put some more compound up there to fill those in. Can I place fresh compound over the PVA, or do I need to prime and sand it before I can apply fresh compound so that the fresh compound bonds well to the surface and doesn't crack later?