Applying a new coat of paint over an older one is common to do when house painting in Danville, especially when you want to update the look of your house. For instance: it’s time for a new look for your home, and one of the renovation projects is to repaint. You’re ready to do it, but you’re stopped by just one problem: you’re not sure if the old paint is latex paint or oil-based paint.
Do not worry, because this article will guide you through in determining whether the old paint is latex (or water-based) or oil-based before you need to apply a new paint.
The general rule of thumb here is that an oil-based paint can be painted over latex, but a latex paint can’t be painted over an oil-based paint. If you try to paint latex over oil, the latex paint won’t adhere properly. Besides, this would be a risky move because the latex paint may cause the oil-based paint to crack and peel.
Oil-based paints have been around for a long time, and it was only during the mid-20th century that latex based paints were created and developed. Nowadays many houses are painted in either oil or water-based paints or both, depending on the room or the type of surface. Although there are many house painters who still prefer the oil-based paints, especially for exterior use, more states are increasingly prohibiting them for indoor house painting.
If you have to paint the exterior walls and trim of your house particularly if it is quite aged (over 50 or 60 years old), it’s safe to assume that they are most likely coated with an oil-based paint.
Here are other ways to know the difference between a latex paint and an oil-based paint that is painted on the walls:
- Know the texture of the paint film after it has been dried and cured. Latex paint tends to be flexible when peeled off the surface, since latex is rubber. Oil-based paints, on the other hand, are not that flexible and are otherwise hard. Your indoor walls are most likely covered with latex-based paint since most of them are less noxious than oil. Oil-based paints, on the other hand, have a tough consistency that is more resistant to impacts, making them suitable for exterior painting.
- Oil paints are generally glassier in appearance compared to latex paints, although some recent latex paints are added with more solids and binders to make them look shiny.
If you are still not sure by just looking at the wall or you don’t want to damage the old walls by peeling a piece of the paint, consider this tip:
- Wet a cotton ball or a cotton swab with an acetone-based solvent or denatured alcohol.
- Rub the dampened cotton on the surface vigorously and with a slight pressure. Do this preferably on the more inconspicuous area of the wall.
- After rubbing, look at the cotton. If you see some color on it, it means that the paint is latex. If the cotton still remains intact, it means your wall is painted with an oil-based paint.
As implied before, latex paint cannot be used over an oil-based paint, but if you have to, you may use a primer first on the walls which are coated with oil-based paints. Some latex paint manufacturers will recommend using a good quality primer over oil-based paints.
Before adding a new paint over the old one, make sure that you have determined if the old paint is latex or oil-based when you are going to do house painting in Danville. You don’t want to end up buying the wrong kind of paint. That will mean an extra trip to the paint store and more time until you can begin. Aside from these tips, you may also want a professional painting contractor in Danville and surrounding areas to ask for further tips regarding this matter.