A question we get asked often is, “Can you paint latex over oil?" The answer is “yes”. But you can't treat it like latex or water-based surfaces. If you put latex paint over oil, you'll end up with that fruit roll-up look all over your house because they just can't adhere.
OIL CAN BE PAINTED OVER LATEX BUT LATEX CAN'T BE PAINTED OVER OIL. If you try to apply latex paint over oil-based paints, the paint will not adhere properly and it will peel off! Here are two examples of Latex paint over Oil-based paint.
The point of an oil primer is that you can then paint anything over it. Painting latex paint over oil paint will end up either peeling off, as shown, or if the oil paint was scuffed/scoured, you can get micro cracking of the paint which shows up and is a pain to get rid of.
The glossy surface of oil-based paint makes it difficult for any other paint to bond. If you apply water-based paint directly over oil-based paint, it will flake and crack as the water-based paint pulls away.
Oil based primer is about as universal a product as exists. Latex, acrylic and alkyd regardless of sheen are all fine on top of it.
Oil-based paints are no longer legal in Virginia and five other states. This is because oil paints create a ton of pollution, both in the air and in the ground. They have a lot of toxic fumes that make them dangerous to be around before they dry, especially for the painting contractors who use them.
Low Odour - water based paint smells much less than oil based. Quicker Drying - most water-based paints are dry within a couple of hours where as oil based paints often take a minimum of 16 hours to dry. Non Yellowing - oil-based paints can start to yellow over time, which is not the case with water-based paint.
Oil over acrylic is fine with certain caveats, but acrylics over oil paints and oil grounds should be avoided. Oil paints form tight, water-resistant films that provide poor adhesion when acrylics are painted on top of them. We recommend avoiding this combination.
If the paint does NOT come off, it is oil-based paint and you will need to prime the surface with a bonding primer before applying latex paint. The primer can be latex, but it has to be a product that is made to prepare the surface and help with adhesion and that says “bonding” on the label.
Best for use in
Use on interior and exterior surfaces including woodwork, drywall, plaster, paneling, masonry, brick, painted metal and properly prepared glossy surfaces†. Use under or over water-based or oil-based paints. Not recommended on flooring.
If you have various stains, shellac Bonding primer is the ideal choice. It can be used to cover rough surfaces and old varnish as well as metal and ceramic.
Oil-based paints also offer a smoother finish than latex paints due to their slow drying times; this allows for a more even coat of paint on your walls without any visible brushstrokes or unevenness in the coverage area. There are some downsides to using oil-based paints as well. One disadvantage is their strong odor.
Extreme dryness can prevent the formation of strong adhesive bonds that allow the innermost coating of paint to stick to the surface properly. Similarly to painting highly humid surfaces, extreme dryness causes any newly applied coats of paint to peel.
It is called the Acetone test. If you have a can of acetone simply soak a rag or cotton ball and rub an area where you think oil paint might be present. If the paint softens or comes off on the rag it's latex if it stays hard and nothing happens it's oil based paint.
The glossy surface of oil-based paints makes it so difficult for any other paint to bond. That's why, if you apply water-based paint straight to oil-based, it will flake and crack as the water-based paint pulls away. So, to get oil-based ready to paint over, you need to take away a lot of that gloss.
In contrast to watering down paint, “thinning” paint is a regular practice for all painters and is recommended by the paint manufacturer. To “thin” paint, an exterior painter will add water to the paint bucket, increasing the paint's workability and slowing down the speed with which it dries.
Oil-based paints allow for greater open-time (or length of time the paint may be brushed before it sets), exceptional flow & leveling (finish smoothness) and resistance to abrasion, once cured.
Here's How To Do It. A question we get asked often is, “Can you paint latex over oil?" The answer is “yes”.
We recommend KILZ KLEAR® Clear Sealer & Bonding Primer – a high performance fast-drying, multi-surface clear primer developed to seal highly porous surfaces inside and outside your home. It is also recommended for use when painting the same topcoat paint color on top of an existing paint coat.
Zinsser Cover Stain 1 Gal. Oil Based White Interior/Exterior Primer and Sealer sticks to any surface without sanding and can be used under and over oil and latex topcoats.
As Moon mentioned, water-based paints have improved greatly and are much more durable, so the need for oil-based paint is virtually nonexistent. Because water-based is now the industry standard, there's a much wider range of products and colors.
Cons of oil-based paint. The main disadvantage of oil-based paint is the strong odour, which is quite invasive, and the paint does take significantly longer to dry, so care is required with any dusty work, and ensuring that nothing is likely to make contact with the wet surface.
Oil-based paints contain volatile organic compounds (VOCs), including known carcinogens like benzene, released into the air as you use them.