Painting for LEED
Earn MR 2.2 Credit – Environmentally Preferable Products
According to the U.S. Environmental Protection Agency (EPA), paints, stains, and other architectural coatings produce about 9 percent of the volatile organic compound (VOC) emissions from consumer and commercial products, making them the second-largest source of VOC emissions after automobiles. VOCs are carbon compounds that evaporate at room temperature and react in sunlight to help form ground-level ozone, an integral component of photochemical smog. VOCs can cause respiratory, skin, and eye irritation; headaches; nausea; muscle weakness; and more serious ailments and diseases, according to the EPA. Formaldehyde, a VOC commonly found in paint, is a probable carcinogen(That’s Cancer).
Oil-based Paints
These paints have high durability and water resistance and are used best in bathrooms, hallways, kitchens and exteriors. These paints usually contain higher VOC’s than latex or natural paints but some oil-based paints now contain less than 100 g/L of VOCs. Mercury-free oil paints are also available; this heavy metals and other toxins should be disclosed on the MSDS. Oil paints typically require fewer coats, which could reduce the total amount of VOCs emitted during the painting process and the lifetime of the painted surface. Oil paints also contain naturally occurring preservatives, so they are inherently toxic to mold and mildew and require fewer additional biocides than latex paints. Oil based paints, like their name implies, are made out of Petrochemicals which are toxic to process and manufacture and the extraction of oil is simply unsustainable. Oil paints contain more compounds with known health effects, such as formaldehyde, toluene, xylene, and benzene, and they take longer to dry, allowing higher concentrations of VOCs to be emitted for longer periods of time. Disposing of oil paints is difficult because they cannot be recycled as latex paints can, but must be “downcycled” into other petroleum-based products or incinerated for energy after they are brought to disposal sites. Cleaning up oil paints typically calls for the use of solvents that release VOCs (though vegetable oil can be used as an alternative to toxic cleaning solvents). There are many other cheaper and more environmentally benign alternatives to Oil paints!
Latex Paints
These paints have water as a carrier which gives them a much a lower VOC output than oil based paints. They do not cover stains as well as oil based paints but there are many high performance latex paints that give them a comparable durability. There are two different kinds of Latex paints, acrylic or vinyl acetate binders. One hundred percent acrylic paint is more water resistant than vinyl acetate paint and is good for kitchen, bath, and exterior applications. Vinyl acetate paint is adequate for most indoor applications and is less expensive. Look for solid content of over 30 percent to hide stains, cover in fewer coats, and cover more surface area per gallon. Almost every major brand of latex paint now has a low-VOC or zero-VOC product line; many of these products are also low-odor. Latex paint cleans up easily with water, so you don’t need harsh VOC-emitting solvents to work with it. It can also be “recycled” by combining leftovers. Using recycled latex paint avoids the manufacturing impact, but recycled paint may not be made of low-VOC paint, so it is best suited to well-ventilated areas like the interior of a garage or shed. Green Seal now has a standard for Recycled-Content Latex Paint that are certified under this and cannot contain more than 250 g/L of VOCs. Some of these paints will contain bio- or fungi- cides which kill mold and mildew but are toxic to human health. Latex paints are biocide free to begin with but almost all manufacturers add synthetic biocides, or “can preservative,” to extend shelf life. Manufacturers are not required to list biocides on a paint’s MSDS because they are added in such small amounts, but some paints are labeled biocide- or fungicide-free. If you do not see this on the label and want to avoid biocides, call the manufacturer to determine if biocides are included in the formulation.
Natural Paints
Made mostly of renewable or abundant naturally occurring materials such as citrus oil, lime, clay, linseed oil, casein, milk, soy and chalk. These paints can create a vibrant, nicely textured, “old world” or “wash” look (particularly lime plaster paints) or a look similar to traditional even-toned paints. Because natural paints do not contain petroleum products, they emit few if any VOCs. The manufacturing process for most natural paints is cleaner than other paint types and some manufacturers claiming that they produce no hazardous waste. Milk-based paint—made from powdered casein, a milk protein—is the simplest, least toxic and least environmentally damaging paint. It contains no VOCs, lead, formaldehyde, oils, or biocides. You can buy milk-based paint premixed or mix it yourself, which saves shipping costs and transport-related pollution. Not all natural materials are safe: for example, cadmium, used as a bright yellow pigment, is toxic and is added to some natural paints. Check the MSDS and ingredient lists when considering natural paints. These paints may contain significant amounts of other VOCs from ingredients like citrus-based solvents, they usually cost 50% more, and may take longer to dry. At this point it is a trade off of human and environmental health Vs costs. In the future, design should bring about natural paints at lower costs than oil based or latex.
“Green Seal” Certification
The GS-11 paint standard developed by the nonprofit organization Green Seal sets comprehensive environmental requirements for low-VOC, low-toxic paints; the standard was updated (with more stringent requirement) in 2008. To be certified by Green Seal, flat paints cannot contain more than 50 g/L of VOCs, and non-flat paints cannot contain more than 100 g/L of VOCs. Low- and no-VOC paints may also contain other compounds that affect air quality. While some of these are known and can be avoided, others are not. Manufacturers are not required to disclose all the chemicals used in their products; some ingredients are deemed proprietary information or are used in such small quantities that they do not have to be reported. Green Seal’s paint certification standards prohibit numerous non-VOC compounds, including heavy metals, carcinogens, and ozone-depleting compounds.
A trusted third-party verification for green paint is paint with GreenGuard Certification.
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