Can you put latex paint on an oilbase or is it the other way around?

Question

We are re -doing our kitchen & before we buy the paint we want to make sure we get it right.The ceilings are an oil based paint & I say you have to repaint them with an oil based product.She says you can paint over oil base with latex.Which one is it?

Answer 1

this is a very good question - and given the responses so far, it's time the facts were set straight...

the simple answer to your question is this: yes, you can put latex over oil...and you can put oil over latex. there are exceptions, of course - and as one responder mentioned, proper surface preparation is the key. but before you listen to someone who is just describing a personal experience - or relating what they think is true paint science - hear my explanation and listen to the logic and reasoning for my statements...(over the next couple of paragraphs, i may use the terms "acrylic" synonymously with "latex" and "alkyd" synonymous with "oil base")

once upon a time, when latexes were not really very good products, they had poor adhesion to any slick surface. therefore, latex could not be applied over an oil based finish with any degree of success...and during this time period (60's & 70's) oil based products were much more prevalent than now. these early experiences became kind of a "truism" for architectural paints regardless of the real facts...

there have been so many amazing advances in "latex" paint technology over the past 20 years, it's unfair to even compare the latex paints of today versus those of 20-30 years ago. manufacturers now use over 100 acrylic and/or vinyl resins (commonly referred to as "latex") in the manufacture of their products. some resins may be slow drying and tacky to penetrate porous substrates and bind in chalk, dust or other foreign matter that'd inhibit the adhesion of most other types of latex products...while other latex resins may dry (cure) extremely fast, have incredible adhesion to glossy, slick surfaces and be very abrasion resistant.

unlike oil based paints, latex paints do not need to penetrate for good adhesion - and the acrylic resins used in high, or premium quality latex products, allow for superior adhesion when applied over surfaces that may be slick or glossy (such as an oil based finish). while it is true that even acrylics will adhere better to a profiled (sanded) surface, it's more important that the surface be clean and free of wax, dirt, dust, grease etc. ...

some "new-age" acrylic products have such good adhesion that they may be used over epoxy surfaces (a harder, more impervious coating than even an oil based coating) without the use of a primer and without sanding...

oil base finishes require some penetration to adhere properly. since latex paints are microscopically porous, penetration will typically occur. the only real limitation on using oil over latex is in exterior use when you have a flexible base coat (latex) expanding and contracting with the substrate beneath a less flexible, more brittle top coat (oil/alkyd) - given the dynamic in that particular example, the top coat will sometimes crack and ultimately peel.

oil based and latex products are very different paint products, each with it's own distinct advantages and dis-advantages. while there have been great advances in latex paint technology, there will still be a market for the advantages provided by oil based finishes. typically, the advantages of latex paints are superior adhesion, ease of application, color-fastness, chalk resistance, flexibility, vapor transmission, etc. ...while oil base finishes have the advantage when it comes to abrasion resistance, impermeability, application over chalky or dusty surfaces, binding loose or dead wood fibers, etc. ...

as one of your responders mentioned, surface prep is the key to any successful paint job. in your case, to paint latex over a gloss oil paint, your ceiling should be lightly scuff-sanded with a medium to fine grit paper - then washed with a non-sudsing detergent* (powder dirtex or soilax, e.g.) to remove any sanding dust, cooking grease, oily nicotine or gas heat residue, waxes, cleaners etc. - allow to dry thoroughly, then paint with latex.

* you can use other detergents, such as t.s.p. (tri-sodium phosphate) or other household detergents, you just need to rinse with clean water after washing surface...

finally, it never hurts to prime...if in doubt, prime. however, the surface preparation for applying a primer is identical to that of applying finish paint. do not use a primer as a means to skip out on surface preparation.

i hope this info is helpful to you...good luck on your projects. feel free to e-mail me if you have additional questions.

ric

Answer 2

You will need to use a primer or the new paint will peel off in short order. Bull's Eye 123 can be used with either oil or latex paints, sticks to anything and isn't expensive. Use one good coat and allow 24 hours to thoroughly dry before putting on the latex top coat.

Answer 3

These days oil based paint is almost nonexistent. Latex over oil is the usual way to go.

However some oil-based paints now are formulated to go over any type of paint. The way to know which is best for you is to read the label of the paint you want to use. The label will tell you what will work or not work.

All of that said, in general latex is far easier to use and cleans up much more easily. When I do paint jobs for interior work I use latex exclusively. Any client that wants oil based for interior jobs will find another painter. There is also the problem of ventilation with oils that you don't need with latex.

Answer 4

Your both right, the key is in preparation. If the old paint is chalky (color or white film comes off when wiped) you will need a special cleaner/chalk remover. The second problem is adhesion. If the surface is slick and glossy you can sand it or try some liquid sandpaper. A coat of primer is never a bad idea, some primers help block stains,and promote adhesion. Go ask questions at a (real) paint store, not Wally World.

Answer 5

You don't want to paint anything painted with oil with any sort of latex finish paint, however there is paint at the paint stores (Sherwin Williams/Ben Moore) that is latex "Bonding" primer which will cover oil and make it pliable for whatever paint you want to go over it with.

Answer 6

Get Zinsser 1-2-3 Primer it will cover over any painted surface even oil without sanding. Drys in 30minutes and ready to apply paint in 1 hour

Answer 7

HI...well since I work in a paint this answer is easy. You CANNOT put latex paint over oilbased paint. So if I were you....I would buy a good primer, put on ceiling, and then paint over this.

Answer 8

Never put latex over oil paint. It will peel right off. You can put oil based over latex.

Answer 9

You can put oil over latex, but not latex over oil, and you still might have to use a primer.

Answer 10

You can use any paint medium as long as you prime things first ask your local paintstore depending on the paint that you choose