You’ve just finished renovating your house or bringing back life to a room with some new paint. Now you’re left with half of an unused can and the question arises: what do I do with the leftover paint?
Since paint can be hazardous to the environment because it contains certain materials that can leak into the ground, contaminate septic tanks, surface, and groundwater, and more, you have to dispose of it properly.
If your paint is not too old, the best option is paint recycling. Check whether your local household waste recycling center has a donation point for paint. Rather than recycling it, they seek to re-use it.
You could also consider donating the cans of leftover paint to a charity, community center, or any other non-profit organization that might welcome the extra supplies.
However, if your paint is too old to be useful, then you should follow the proper steps for disposal. Different areas may have different requirements and restrictions, so be sure to mind them.
For general steps on how to store and dispose of old paint, keep reading this article!
How should I safely dispose of latex paint?
If you can’t take your latex paint to a recycling center, then you have to let it harden before you can dispose of it. Water-based paints are not considered hazardous, but they still shouldn’t be dumped on the ground, poured down the drain, or into a garbage bad while liquid.
For small amounts of paint in the bottom of the can, leaving it out in the sun for a few hours is enough. Make sure to leave it somewhere small children and pets can’t reach it.
For larger amounts, there are a few other options:
- Cat litter, sawdust, or shredded newspaper: add equal parts cat litter, sawdust, or shredded newspaper to the latex paint in the can to aid in clumping it up and drying up faster.
When there’s more than half a can left, you can pour the paint into a lined box or trash can, then pour in the cat litter, sawdust, or shredded newspaper.
Stir the mixture until it thickens and let it sit for at least one hour. Once it has fully dried, you can throw the can in the garbage. The lid should be disposed of separately, and preferably recycled to reduce landfill waste.
- Paint hardener: there are commercial waste paint hardeners that you can purchase at your local hardware store or home improvement center. They work faster than cat litter and newspaper, and you just follow the manufacturer’s instructions.
As you can see, latex paints are the easiest to dispose of. You only have to let the paint harden before throwing it away.
How should I safely dispose of oil-based paint, solvent-based paint, and paint thinner?
Oil-based paint, solvent-based paint, and paint thinner are considered hazardous waste due to their flammability. They cannot be poured down the drain or hardened and taken out with the trash.
They must be disposed of at specific hazardous waste collection sites or drop-off centers. You should check with your local officials about instructions for safe paint disposal.
How should I store old paint for disposal?
If you’re sure you’re going to dispose of your old paint, you can simply keep it in the can and let it harden—as long as it’s latex paint. When there’s more than a can left, and you need to mix the paint with cat litter, for example, you can line a cardboard box or a trashcan with plastic.
For oil-based paint, you should make sure to replace the lid firmly to prevent any spilling.
Are there any alternatives to disposal?
As we’ve mentioned at the beginning of this article, donating your leftover paint is a good alternative to disposing of it. However, this only works in most cases for latex paints, as many places don’t accept oil-based or spray paints.
Some other options are:
- Use the excess paint for other projects. Re-coating, touch-ups, or painting a closet, garage, basement, or other places that don’t require a perfect painting job are all good ways of using your leftover paint. You can even use it for DIY projects!
- Return extra cans to the store. If you have unopened cans of paint, you can ask the store if they’ll accept them. Some companies have a recycling program through which they remix and repackage the paint.
How do I know if the paint has gone bad?
It’s quite easy to know if your paint has gone bad. If it has expired, it comes to reason that you should better dispose of it. However, if it feels hard, thick, and lumpy, or if it has a particularly foul smell before the expiration date, then it means that it has probably gone bad. This usually happens because of improper storage.
These characteristics of paint gone bad shouldn’t be confused with paint skinning. If you open a can and notice that the paint has separated or that a “skin” has formed on the surface of the paint, you shouldn’t worry as it’s a normal occurrence.
Water-based paints, in particular, are prone to skinning. Higher temperatures and exposure to sunlight, as well as a poorly sealed lid, are some common culprits of skinning paints. To fix the paint and make it usable again, you only need to remove the skin and stir the paint.
What is the shelf life of paint? How can I store it so it lasts longer?
Stored in optimal conditions, the shelf life of latex paint is approximately 10 years, whereas oil-based paint can last for up to 15 years.
The optimal conditions for paint storage include leaving the paint in its original container and placing it in a cool, and dry place where temperatures are above freezing. Freezing and thawing can greatly reduce the shelf life of latex paints.
Keep the can away from sunlight and out of reach of small children and pets.
You should avoid storing paint cans directly on cement floors because this material makes the bottom of the can rust faster.
We recommend that before storing it, you wipe away any excess paint on the rim and the outside of the can in order to avoid it getting sealed shut with dried paint.
To prevent paint skinning, you can place a piece of plastic wrap between the opening and the lid, and then seal it with light taps from a rubber mallet. You can use a hammer, but you have to be extra careful and cover the can with a piece of wood and then hammer the lid shut. This way you won’t damage the can or bend the lid, which would make it harder to open and close in the future.
It’s highly important to replace the lid firmly and leave the can upside down to prevent air from entering.
Proper paint disposal is essential to avoid damaging the environment. Latex paints are easy to dispose of, you need only to let them harden. You can aid it by mixing a commercial hardener with it or by adding cat litter, sawdust, or shredded newspaper. Oil-based paints, on the other hand, are considered hazardous materials and must be disposed of at specific hazardous waste collection sites.
Paint that’s been stored in the proper conditions can last for many years. But even if you do want to get rid of your leftovers because you don’t want the unnecessary clutter or don’t have enough space, we’ve given you some cool alternatives to disposing of it.
No matter what you choose to do with your excess paint, make sure you do it safely!