Last month I decided to spray paint the new ceramic pots I bought for my Purple Heart plants. Since I already had a can of ice blue spray paint that I purchased 4 years ago, I decided I didn’t need a new one. But as I started painting, I realized the color was much darker, and the nozzle kept giving up on me. That’s when I realized that my spray paint had expired.
Yes, usually spray paint expires in 2-3 years, but the duration varies between brands. The best way to determine whether your spray paint has expired is to check the expiration date on the bottom of the can.
Sometimes, you will find that your paint hasn’t expired, but it’s still not giving the same results as before. That’s because spray paints can go bad even before their expiration date if not stored properly. With my help, you can learn how to get the most out of your spray paint investment.
Does Paint Have An Expiration Date?
Many DIY enthusiasts have different colors of spray paint lying around in their garages. However, before you start using them for a new project, you should check their expiration date.
Every spray paint has an expiration date that you can check at the bottom of the can. Usually, every can has two dates: production and expiry, and if you look closely, you can easily identify both. The expiry date is generally written as Month/ Day/ Year. So if your paint expires on July 1, 2023, it will be printed as 7/1/23.
How To Know If Spray Paint Is Expired?
The spray paint expiration date is the most effective way to determine if your spray paint has gone bad. However, inappropriate storage conditions can also cause an adverse chemical reaction in the paint and affect its consistency.
The following are telltale signs that your spray paint can has expired:
- The paint has turned a different color than when it was new.
- The nozzle of the can is clogged or rusty.
- The paint has started to separate.
- The application is not smooth, and the nozzle keeps clogging up as you spray.
Does Spray Paint Go Bad Before Expiry?
If you’re wondering, ‘does spray paint expire if not opened?’ the answer is no. Storing your sealed paint in ideal conditions can make it retain its original position for years. Sometimes, you may notice that the can has developed a hard lid, but that can be easily reversed by softening it with hot water or a hairdryer.
The lid usually hardens when the solvents inside the paint have evaporated, but that doesn’t mean it’s unusable.
After you’ve opened a spray can, environmental stressors, such as high heat, humidity, etc., can cause the paint to go bad.
Especially if the paint has been sitting for a long time, it’s possible that its propellant has evaporated or the nozzle is clogged. At times, the formula of the paint changes or its potency reduces over time, which means it may not deliver the same results as when it was new.
What Causes Paint to Go Bad?
Several factors can affect spray paint’s formula and mechanism. If you’re not careful enough, the following factors can reduce spray paint’s shelf life and affect its quality.
Extreme Temperature
Any area that receives too much heat or cold is not an ideal storage place for spray paint. The paint inside will dry and crack if the can is exposed to high temperatures. So, when you press the nozzle, nothing will come out.
Placing it in a cold spot will also affect the paint’s quality, making it go bad before the expiration date.
Exposure to Direct Sunlight
Direct exposure to sunlight can be harmful for your spray paints. If you keep your spray paint cans where they are exposed to direct sunlight, the chemicals in the paint’s formula will break down, causing it to become dry and brittle.
The paint will also lose its color if it’s wrongly stored directly under the sun.
Humidity Levels
Too much moisture in the air can upset the composition of the spray paint. This can make the paint inside sticky and lumpy. If you are not careful about high humidity levels in the storage area, your paint can go bad and become unusable.
Reduced Aerosol Pressure
If you open a spray paint can but don’t use it frequently, the aerosol pressure inside the can reduces over time. In this case, the paint’s formula is usable, but because there’s no pressure in the can, the spray mechanism won’t work.
Environmental Impurities
Whenever you use spray paint, environmental impurities such as dirt, oxygen, and ultraviolet rays enter the can through the tube. When these impurities get mixed with the chemicals inside, it causes an adverse reaction that makes the paint go bad even before its expiration.
Can You Use Paint That Has Gone Bad?
Sometimes, your spray paint can go bad even before its expiration date, but that doesn’t mean you should toss it away immediately. You can follow the tricks below to revive your old can and make it work.
1. Shake It Well
If you’re using an old can and nothing is coming out, try giving it a thorough shake for 2-3 minutes and use it again. Most of the time, this acts as a ‘jump start’ for spray cans as it’s jolted back to life after sitting on the shelf for too long.
Shaking the can also help mix the color pigments that get settled at the bottom due to infrequent usage.
2. Immerse In Warm Water
If you find that your spray paint is coming out too thick, you can immerse it in warm water to thin it out. Once the paint returns to its normal consistency, the application will become smooth and even.
3. Decant the Paint If the Aerosol Isn’t Working
Loss of aerosol pressure is common in spray paints, but why throw the can away if the paint inside is usable?
Simply decant the paint by gently making a small puncture near the top of the can. Once the remaining pressure has escaped, you can cut the can open and transfer the paint into a sealable jar or a spray gun jug.
It would be best to stir the decanted paint before using or storing it to help release any gas or propellant that may still be inside.
FAQs
Does spray paint expire or go bad?
Spray paints usually expire in 2 to 3 years, but if they’re not properly stored, they can go bad before expiration.
How to dispose of spray paint safely?
A safe way to dispose of empty spray paint cans is to puncture a hole and recycle it as scrap metal.
How long does unused spray paint last?
An unopened can of spray paint has a shelf life of 2-3 years from its production date if stored properly.
What happens if you use expired spray paint?
If you use expired spray paint, the result will be vulnerable to drying and cracking. Also, its application and color may be different.
Final Word
It can be frustrating to find your spray paint can unusable after you have prepped the surface. Therefore, you should check your old cans’ expiry and test them before starting a new project to avoid any surprises.