How To Tell If Old Paint Is Still Usable?

We all have a couple of cans of paint floating around our homes somewhere. Maybe it’s that can of bright red you thought you would be bold with, and then changed your mind. Or maybe it’s a half can of white you keep around for touch-ups that rarely get touched up. Since there are so many projects to do with leftover paint, you may be wondering: is this old paint still usable? If you’re wondering how to tell if your paint is off, you’re in the right place, but first, let’s understand if paint really goes bad or not.

Does Paint Go Bad or Expire?

Yes, paint can go bad or expire. How long the paint is going to last depends on how you store it and the base of the paint. If it’s an unopened paint, it tends to last more than the one that was exposed to weather conditions. Just like oil-based paint will probably last longer than latex and water-based paint. Check how long paint can last for each scenario below:

Unopened Paint

The good news is that if you have an unopened can of paint that has been stored properly, it’s almost guaranteed to still be fine to use. Unopened latex and water-based acrylic paints can last up to 10 years and alkyd and oil-based paints can last up to 15 years. Unopened paint maintains its ratio of liquids and semi-solids which is why it’s fine to use after a long period of time. Once the can is opened and exposed to air, this ratio begins to change.

It’s important you test a small patch before you plan to use that can of 5-year-old paint in your home. Since the paint has been sitting for so long, it’s likely it has separated. You will have to blend the contents thoroughly with a paint stirrer for at least five minutes. Stir up the paint and then test it on a piece of cardboard. If the paint looks normal and goes on smoothly, then you’re ready to start painting! If you notice lumps or grainy bits that you can’t stir out, the paint’s chemical makeup has changed and it cannot be used.

Opened Paint

If the can of paint you want to use is opened, there may still be hope. When paint is exposed to the air for long periods of time, it changes the chemical make up which is why old paint cannot be used sometimes. To check if yours is okay, you will have to open the can and stir up the contents. Before you do, be sure to remove the layer of thickened skin on the top. Once this is gone, you can stir the paint and then test it on a piece of cardboard. If the paint goes on normally, your old paint is safe to use! If not, another trip to the paint store is in order.

Paint Exposed to Weather

If you’ve been keeping a can of paint on your back porch or in your garage for several years, it’s likely the paint is not in the best condition. This is because paint cannot handle being exposed to extreme heat and cold. Even fully sealed contents may not survive our Canadian weather. It’s worth doing the paint test described above just to check. Remember that smooth paint is fine to use, but if it’s lumpy and grainy you’ll want to purchase a new can.

Below you’ll find the average costs of Paint & Wallpaper services across different cities in Canada:

*Costs based on 13,969 verified Canadian homeowner reviews as of March 2022

What are the dangers of using old paint?

Yes, there are some dangers associated with using old paint in certain scenarios. If your paint is from 1990 or earlier, it might contain lead or mercury, which can be harmful to your health. However, as long as the paint is smooth, it’s unlikely to pose any health risks, making it still usable after years of storage.

How Homestars Can Help You?

Now that you know how to check if your old paint is still usable, it’s time to get to work and start painting. If you would rather have someone else do the hard part for you, you can easily and quickly find a painting company on HomeStars. Whether you end up using your old paint or buy new, you’ll be happy someone else is doing the work for you!

Article Updated April 2024.