Oil Paint on Plaster
I'm refinishing a sunroom, circa 1920, that has been painted with oil based paint. It appears that no primer was used and some of the paint is flaking away from the plaster walls. If I sc**** and sand the flaking areas is there a primer that will seal the whole thing so I won't have to worry about further flaking under the new paint?
Thank you for any ideas
Re: Oil Paint on Plaster
Plaster has a very hard slick surface. It was normally primed with an oil primer in years gone by. The most common reason for the bond having been broken is some moisture involvement such as a water leak. Usually this is accompanied by some brownish staining, or if severe, by the finish plaster de-laminating from the scratch coat plaster ( the rough gray plaster underneath ).
When patching such peeling, I liked touse drywall topping compound. It has better adhesion than some other patching products such as "Spackle", when applied and feather in very thin coats.
After sanding, you will need to prime. An oil primer will lessen the chance of water stains bleeding through. Also, if water was involved, the oil has a lesser chance of causing further peeling
of the badly adhered paint. You can then procede with acrylic paint as your top coat.