Painting the inside or outside of your home is challenging but fun, and when you are finished, you often have at least small amounts of paint left over. Since we are becoming more and more conscious of recycling efforts nowadays, many of us wonder what to do with our leftover paint. Below are a few tips for recognizing when it is time to throw out the old paint and how to properly dispose of it.

First, Test the Paint

If you have paint cans that have been around for a while, especially if you are unsure how long they have been there, you can easily test them to see how good they are. Open the can of paint and stir it well, then brush some of the paint on an old piece of newspaper. If it is anything but smooth—for instance, if it has lumps or is inconsistent in its texture—it is time to get rid of it. If the paint is still good, it will be very smooth. If not, toss it.

How Long Are Paints Good?

Like most products, there are time limits for paints, and a lot of their longevity is affected by the type of paint it is and the length of time it has been stored. As a general rule, oil-based paint is good for approximately 15 years, but only if it is still unopened and has been kept away from extreme temperatures. Water-based paint is good for up to 10 years under the same conditions. However, if any paint can have been opened and used, it should be closed tightly and kept in cool and dry locations. All used paints, moreover, should be thrown out after two years.

Occasionally, regardless of its age, the paint will become spoiled, meaning that when you stir it, the liquid and solid portions do not mix. If there is a hardened material on the bottom of the can, a foul odor, or visible mildew or mold, the paint has spoiled and should be discarded, regardless of how old it is. When it doubt, throw it out—it’s just that simple.

What Should You Do with Old Paint?

Discarding old paint is a little tedious sometimes, but it is much easier if you keep in mind certain rules:

• For latex and acrylic paints, mix them with cat litter before discarding them. Mix one part paint and two parts clay-based cat litter, then stir well. After roughly an hour, they should be solidified, and at that time they can be thrown away.
• For oil-based paints, you should always check with your local or state environmental protection agencies, because these are considered toxic waste and should be discarded accordingly.

Many of us have old paint in our storage room or garage, but most of it is easy to discard once we learn a few basic facts. Research the types of paint you have and follow the tips above to easily and properly dispose of any of your old paint.