HOME REPAIR TIPS
Painting Tips & Tricks: Do I Have Latex or Oil?
Since it’s difficult if not impossible for the average homeowner to determine from a visual inspection whether they have latex or oil paint on their walls or trim, I’ll share a simple test that can easily confirm the type paint. Many older homes, and all homes built about 50 years ago were painted with oil paint—latex paint wasn’t generally available until the 1960s.
Oil, paint, as the name implies, was first made with linseed oil; now, however, the oil used is synthetic or “alkyd” based. For the first few decades after the introduction of latex paints, oil maintained its superiority for many applications; however, recent innovations and improvements in latex makes it nearly equal, and in some cases superior, to oil or alkyd paint. And, with environmental concerns, latex and the next generation of low VOC (Volatile Organic Compound) paints, the future of oil paint for residential use is in doubt.
While many paint experts can accurately determine the type paint used by examining the surface, the average homeowner cannot. There is, however, a pretty reliable test that can be used to identify paint types.
Scrub a small spot with a detergent/water mix, then rinse and dry. Using a small rag dampened with denatured alcohol, acetone-based nail polish remover, or Goof-Off and rub the area vigorously. If the rubbing removes the paint, it’s latex or water-based; if not it’s oil. Latex paint will also feel “tacky” to the touch following this procedure.
It’s important to know the type of paint on a surface in order to determine the preparation necessary for recoating. Generally speaking, you can use latex paint over oil, but should not use oil over latex. The reason is purely adhesion, how well the new paint will adhere to the old surface.
Regardless of the type paint on the wall, some preparation is necessary prior to painting in order to create a lasting finish. The best procedure is to describe your particular situation to a paint expert at your local paint store or home center. They can guide you in paint and primer selection and can make suggestions to make the job easier.