Probably one of the easiest and most affordable ways to refresh your space is to slap a coat or two of paint on the walls. However, walking into your local hardware store or big box home improvement store and coming to aisles full of paint cans can be overwhelming. I’m certainly no expert on all the types of paint and what exactly you should choose for your particular application, but I can tell you how to choose an environmentally friendly paint.
Oil Based vs. Latex (Water Based)
The first question to address when choosing and environmentally friendly paint is whether to go with an oil based paint or a latex paint.
Oil based paints are slower drying which can provide a smoother finish, as any pools or ridges will have a chance to settle before the paint is completely dry. Oil based paints also can have better coverage, which means fewer coats, and can hold up better over time. However, oil based paints require more harsh chemicals to keep the colors suspended in the paint. Not only do oil based paints require special disposal at a hazardous material collection center because of these harsh chemicals, but they also give off a lot of fumes. These fumes are dangerous to breathe in. Oil paints also require harsh chemical solvents for clean up.
Latex, or water based paint, dries faster, can be fairly easily cleaned with water, and resists yellowing over time (another common issue with oil based paints). Latex paint contains fewer hazardous chemicals than oil based paint, but still contains some and can release harmful fumes. Latex paint should not be dumped down the drain, or just put in the trash in its liquid state, but if it needs to be disposed of, it can be dried up by soaking it up with kitty litter, newspaper, or sawdust.
When given the option between oil or latex paint, the more environmentally friendly paint is latex paint.
Volatile Organic Compounds (VOCs)
The harmful fumes given off by paint are due to volatile organic compounds, or VOCs. VOCs are emitted gases that can cause a variety of health problems when breathed in. VOCs can be found in paints, household cleaners, adhesives, pesticides, and building materials among other things. In paint, the chemicals that make up VOCs are used to hold the dyes suspended in the paint. After the paint is spread, the VOCs evaporate out, and the color stays in the dried paint. The US government has created a standard of 250 grams per liter of VOCs for flat paints and 380 g/l for other finishes. However, California, a state that frequently enacts stricter environmental regulations, has capped VOCs at 50 g/l for all finishes. Paints that adhere to the California regulations typically label themselves as Low-VOC. (It’s important to note that in order for a paint to be labeled low VOC, it only has to contain less than the government standards. You should read the label carefully to see the reported number of VOCs each brand and finish of paint contains.)
More recently some paint brands have advertised certain paint lines as being no VOC. In order to do so, they must contain less than 5 g/l of VOCs. Some paint brands have also opted to get evaluated by third party certification programs such as Greenguard or Green Seal to set themselves apart as environmentally friendly paint choices. These certifications evaluate the paint on more than just VOC levels as well and award their labels to paints that meet their environmental standards.
To choose a more environmentally friendly paint, look for low- or no VOC paint options, or paints that have received Greenguard or Green Seal certification.
There are some paint options that do not contain the harsh solvents used in oil or latex paints. These paints are instead pigmented with naturally occurring materials such as clay, lime, linseed oil, or chalk. Natural paints do not contain VOCs, but they do come with drawbacks. The color choices are limited, drying time can be long, coverage can be not great, and they are typically significantly more expensive than latex paint. You can find information on making your own natural paint and a list of natural paints here.
If you want to make the most environmentally friendly paint choice, and your needs can be met by the limitations above, look for natural paints.