How Can I Get Rid Of My Old Paint In The Garage?

How can I get rid of my old paint in the garage?  This is a great question I have answered before however with not a lot of in-depth information.  This time I will delve deeper into this answer.

Preface:  To start with there are some tall tales that are a myth about preserving the leftover paint.

1. When you have, let us say, half of a gallon of paint left over and want to store it for some extended period of time, you just put the lid on tight and turn the paint can upside down.

That doesn’t work.  The reason is that when you closed the lid you also trapped in oxygen inside the empty space of the can.  Then when you turned the can upside down the oxygen is still trapped in that container and oxygen starts to dry the paint.  A year later when you go to use the paint for touch up, the paint is lumpy or dried.  Rendered unusable.

2. When you have leftover paint that you have had in a roller pan a roller, in a brush and a paint bucket all of which you have scraped or pored back into the original paint can.  You have just contaminated the can of paint that you will want to use at a later time.

With the closed lid, half full of contaminated paint and the empty part is filled with OXYGEN.  This becomes a concoction that will mildew rapidly.  Because where do you think you are going to store this vile can … IN THE HOT GARAGE.  The perfect storm becomes an incredible smelly touch-up paint in the future.

You see, the use of the brush, roller, buckets and roller pan all contain some sort of bacteria that you have picked up from the surfaces you were painting. Then you put the leftover paint back into the original paint can and stored in the hot garage which causes rapid mildew growth at a rate that has been explained to me, with spore growth that is countless.

One caveat to this dissertation is you can pour into the leftover paint a couple of tablespoons of bleach that will prevent the spores from growing.  This process will not cause any harm to the paint.  Furthermore, if you discover that a can of paint you were going to use for touchup is very smelly and moldy after the fact, you can put a few tablespoons of bleach in the leftover smelly paint then stir it up and let stand for a day.  At least the paint will not smell when applied again.

I have been an expert witness for paint disputes for years and one case was that a large bank lobby was painted with leftover paint from a larger contractor paint job.  The contractor was trying to cut corners and use leftover paint from a previous large paint job.  The paint from that job was poured back into buckets each day for a week.  Then the paint was stored in a hot warehouse for a few weeks and then used on the new bank lobby.

Because of the new construction of the bank lobby the fresh air was masking the mildew smell each day.  However the next week the lobby was reopened and the enclosed air system caused the mildew to become obnoxious.  The bank called me to evaluate the situation and when I discovered in the storeroom a touchup can leftover from the paint job that the touchup paint was contaminated with mold and mildew.  This contaminated paint was spread thinly over the whole surface and the smell wasn’t going away.

The job needed to be repainted however it was necessary to mix in bleach with the new coating to combat the mold on the existing sub straight.

NOW TO ANSWER THE ORIGINAL QUESTION!  Leftover paint can be thrown away however it needs to be DRY before doing so.

This is what you can do.

  • You can pour the wet paint on lots of newspaper and let dry, then throw in the trash.
  • You can mix in cat litter and spread out on newspaper, let dry and then throw in the trash.
  • You can buy in most paint stores an additive that hardens latex paint and then you can throw into the trash.

  • Oil-based paint will take longer to solidify or dry, the newspaper can be used then throw into the trash.

The most important factor about throwing paint away is that it needs to be DRY.  No liquid vehicle should be remaining.

NOTE!  If for some reason you have some paint that you want to dispose of that was made prior to 1978 you need to be very careful.  That paint may contain lead.  Lead is something we do not want in the landfills.  If this is the case you will need to contact a ‘Lead Abatement Contractor’ to dispose of this product.

If you suspect Lead, contact the EPA’s website for instructions.  Environmental Protection Agency

I hope this answers your question!