For simplicity, the term "latex" will be used in this article to describe water based paint because it is the most commonly used term. There are more accurate ways to describe certain types of water based products but we will not go into that today.
When I am in a customers home, I can usually figure this out by sight and touch but sometimes it can be hard to tell if the finish is oil based or latex. This is most often a dilemma associated with trim work and doors since this is where oil based was used often when it was popular.
Oil based paints were used because of their durability and self leveling properties. VOC (volatile organic compounds) regulations have put a screeching hault to the widespread use of the product. They can still be found and applied, but it will most likely be found in a quart can and with a hefty price tag.
Here is a low cost way to figure this out on your own:
Reach into your cabinet for some rubbing alcohol or nail polish remover
Put some on a clean rag and rub the surface in question back and forth
If the paint starts to come off, you have latex paint, if not, you have oil based paint
So you have discovered that latex paint is on your surface....Woohoo!! Congratulations, you now have minimal preparation before you can apply latex over the old coating. I would recommend a 100% acrylic paint for that.
Your findings show that you have oil base paint? Do not fret. There are several ways to go about repainting over oil:
Stick with oil base. If you can handle the price tag and the slight odor, this can be the simpliest solution.
Prime with an oil base primer and topcoat with a latex paint.
Use a product called Oil Bond. You use this product by wiping it liberally on the surface, let dry for 1 hour, add the directed amount to the finish latex paint, mix and paint away!
Arey Painting can be at your service if you still require help. Please don't hesitate to call us @ 410-341-0605 or book your estimate online via our website.