What will happen if you paint latex over oil paint, without priming or sanding?
By teddy99 from Toronto, ON
You can put latex over oil, (because oil is hard and doesn't move or "stretch"), but you can't put oil over latex (because latex is made with a "rubber" compound and stretches and is slightly pliable). But they never go into detail about it so you hear that you should never put one on top of the other (this way people won't get mixed up).
But you'll never go wrong with using a primer, especially one that's tinted to match your paint. This way you'll only need one coat of primer and one coat of paint instead of 2 coats of paint. If it were me and especially if I wasn't using primer, I'd use 100% acrylic paint (see * below). Even if you use a primer you should still never put oil over latex (but you can put latex over oil). Remember to de-gloss any semi-gloss or glossy paint or your paint won't stick properly.
Professional house painters have told me that because latex (and acrylic) stretches slightly it makes a longer lasting paint for the outside of homes (because of the massive heat/cold temp change that happens on the outside of homes), ever since they've taken lead out of paint. Lead was added in the old days to make the oil-based paint more playable and longer lasting, but these days it's latex and not oil that last longer on the outside of homes because they've (thankfully) removed the lead. Others may disagree and say that oil paint lasts longer, but this is what I've been told and it makes sense. Oil probably does last longer when temperature fluctuations aren't a factor.
Read more details here:
* 100% arylic paint: I'm a professional artist and mural painter and often recommend different types of paint to go under my work as a base. Most people don't know that you can buy 100% acrylic indoor or outdoor paint in all sheens for the same price as latex paint. Gallons of 100% acrylic paint are usually only recommended for painting masonry (like brick, cement, and stone work) because 100% acrylic tends to adhere much better than latex. But it's a much better paint, and for the same price as latex I would always buy 100% acrylic paint instead. It's available in all the same colors as latex or latex-acrylic. So next time you want a quality paint, ask for 100% acrylic. It's not just for painting masonry! Acrylic is water based, has no bad scent, dries quickly and it's durable, flexible, and washable too. (07/03/2009)
Our tenants did that in our rental house. The latex paint would then scratch off with just about any touch. It is not a good idea to paint latex over oil. I think if you Kilz it first you can then paint over it. (07/07/2009)
My dear eX-hubby was asked to pick up some oil based paint for my kitchen. I even gave him the $$$ for it! He came home with latex paint because it was cheaper (I never saw the extra $!). Anyway he insisted that I use the latex paint over the oil paint that was on the walls. What a disaster! It took exactly 2 days before the latex paint started peeling off the walls in strips and chunks! I had to hire a professional painter to come in and scrape and seal all the walls, and repaint the whole kitchen! It cost me an arm and a leg! Never, never put latex over oil! (07/07/2009)
Add your voice! Click below to comment. ThriftyFun is powered by your wisdom!