Oil-based paint once ruled the world of interior paint for high-impact areas such as trim work, doors, and cabinets. When it dries, oil-based paint emits a host of VOCs (volatile organic content) that are harmful to the environment. The paint is often messy and smelly since mineral spirits or paint thinner must be used for clean up, not water.
If a house is old enough, it will likely have oil-based paint somewhere, since water-based latex paint wasn’t introduced until the 1940s. And newer houses might have some areas of oil-based paint since it is not entirely banned: Oil-based paint is still available in quart sizes or smaller. Many professional painters even favor oil over latex for a smoother, rock-hard finish that leaves no brush marks, gaps, or bubbles. You’ll typically find oil-based paint used on door casings, trims and moldings, mantels, cabinetry, and shelving.
Can You Paint Over Oil-Based Paint?
Latex paint (and even other oil-based paint) can be successfully applied over older oil-based paint as long as the surface is fully cured and there is nothing inherent in the coating that prevents another layer of paint to be added.
Preparation is important. Glossy surfaces will not take a second layer of paint well, so they need proper cleaning and priming. You can achieve that by following these steps.
Before you begin painting, make sure to get enough paint to finish the project with the help of The Spruce’s Paint Calculator.
Source: The Spruce