For years, I stored all of my leftover paint in the garage. We had several shelves full of half-empty gallon and quart size cans. About this time last year, I decided that needed to change. Not only were they taking up valuable garage space, but it turns out that paint goes bad after being stored outside for just a short while. I felt silly for not realizing that.
So instead of storing the new cans I have more recently acquired in the garage, they now take up residence on top of the cabinets in my laundry room. It’s a great solution for the new paint, but I was left with a conundrum of how to dispose of the old paint. You shouldn’t simply throw it out with the weekly trash, as it presents a hazard to the sensitive environment.
In many areas, you can take your half-full cans of paint to be disposed of in hazardous waste collection facilities or recycling centers. You can find a place in your area by visiting Earth911.com.
It’s also quite easy to harden leftover paint to make it okay for curbside pick up. Now, I’m certainly no expert, but I understand that most municipal trash pickups will collect dried latex paint. I have heard that you can use mulch or cat litter to harden the paint, but I just picked up a package of Homax Paint Harder for a few dollars at Home Depot.
To use the paint hardner, you simply dump the powder into up to 2/3 gallon of paint. I had about a quart of paint in a plastic box that I needed to harden, so I just poured the powder into it.
With a stir stick, I stirred the powder into the paint until it started to thicken up.
After about 15 minutes, it had hardened to the consistency of thick oatmeal. The wonders of chemistry!
At this point, you can simply scoop the hardened latex paint into something like newspaper and throw it away on trash pickup day. Your cans can then be recycled.
Oil-based paint cannot be disposed in the same way. Instead, it does need to be taken to a local hazardous waste facility.
Now I just need to buy about 30 more packets of paint hardner to finish up the rest of the paint left in the garage! What do you do with your leftover paint? Have you ever used a paint hardener?