If you live in an old house, chances are that YOU didn’t paint many of the things inside. You might have changed the color on your walls, but if you have painted cabinets, bookshelves, doors and trim how do you know what kind of paint that is?
I have a bunch of printed trim in my house that needs to be fixed up. In fact, something is soaking through the paint. I don’t want to just paint another layer over the old paint without knowing what it is first because the results can be disastrous.
First I’ll share a quick tip for how to tell if your paint is oil or latex and then I’ll share tips for how to paint over oil paint with latex and get good results long term. It is possible, but you have to take special prep steps.
Easy Way to Tell If Your Paint Is Oil Or Latex
The best way to tell if your existing paint is oil or latex paint is to use alcohol or methylated spirits (also called denatured alcohol). You can do this with a cotton ball unless you are testing white paint. You simply wet the cotton ball with rubbing alcohol or methylated spirit and rub it up against the paint vigorously for a few seconds. If paint comes off onto the cotton ball or cloth, it’s latex paint.
If you are looking to paint multiple doors in your home, be sure to test each one. You might be surprised that some doors or rooms are painted with latex and some are painted with oil. Again, you never know if they were all painted at the same time.
If you are trying to test white paint, use a colored cloth so you can easily tell if white paint is rubbing off.
Can You Paint Latex Over Oil Paint?
If you paint latex paint over oil paint without prepping properly the paint will easily chip off. Oil paint does NOT adhere well to latex paint. If you want to use Latex paint over oil follow these two steps before you start painting.
I choose every product I review. I may earn an affiliate commission if you buy from one of the product links, at no extra cost to you. This income supports this site. See the full disclosure.
- Rough up your paint using a fine grain sand paper like 220 or 320 grit. You don’t need to spend a lot of time sanding, just a light sanding to roughen up the surface a little bit.
- Use a primer (if you have time, 2 coats are better than one). I like to use this Zinsser Bullseye. It is low odor and works well over oil paint.
Advantages of Latex Paint
Latex paint has become more prevalent because there are lots of advantages to using it like:
- Easier cleanup during your paint job
- Low odor and less fumes
- No yellowing (if you’re painting white)
- Dries faster
The disadvantage of latex paint are that it isn’t as sturdy as oil-based paint. Latex paint chips and scratches more easily. Oil-based paint is also easier to clean once it’s on the surface (not during the painting), which is why it is often used on wood trim, doors and cabinets.
Next time you are getting ready to paint an old door or touch up some of the wood trim in your house, be sure to test the paint first. It might require some extra prep work if it’s oil-based paint.