Since the Clean Air Act became law in 1970, it has been used to regulate the content of volatile organic (VOCs) in a variety of products and manufacturing processes, including architectural coatings. That section of the federal law initially focused on the release of VOCs into the outside air as ground-level ozone, a key contributor to smog. Today, the popular focus for reducing VOCs in the built environment has turned inside, including the impact of house paints and other coatings on indoor air quality and the health and comfort of contractors, homeowners, and building occupants.

The result has been, and continues to reflect, a sea change in manufacturing technology. Initially reformulated to meet or exceed varying standards governing VOC emissions, low- and no-VOC water-soluble latex and natural paints now also satisfy the growing demand for healthier and environmentally benign alternatives to conventional coatings.

The Value of VOCs

VOCs in water- and oil-based paints are carbon-containing chemical compounds used as solvents to thin and bind the solid content and pigments, and as coalescent to help the latex resins flow together toward the formation of the finished surface coat. The coating applies smoothly and evenly, hides brush strokes and the substrate being covered, and maintains a desirable durability, among other benefits.

The compounds readily and completely evaporate into the air as the coating is applied and cures, usually within a few days. Inside the home, in high concentrations and because they are often “trapped” within a structure, VOCs give off a distinct and lingering smell. Emissions also are slower to dissipate than in exterior applications, potentially affecting the eyes, nose, skin, and lungs of the painter and the occupants.

Performance Improvements

Early attempts to reduce VOCs in paints focused primarily on the amount or ratio of solvent to solids and pigments in the mix. As a result, initial solutions dried faster (per the higher percentage of water and solids to solvent), covered less area, and were less durable to regular cleaning than their conventional counterparts.

Three decades later, low- and no-VOC formulas are nearly comparable in performance and price to their predecessors, thanks to advances in coating chemistry.

“In the past, contractors had to make a choice to pay more and sacrifice quality when using a low- or no-VOC coating,” says Tom Dougherty, director of brand marketing for PPG, maker of Pittsburgh Paints and other brands. “Today, they don’t have to make that choice, and paint professionals are hard pressed to notice much of a [performance] difference now.”

That, and they’ve also adapted to low-VOC paints. “Contractors have learned to apply in smaller sections, to work faster, and not overwork the coating, and to apply it thicker,” says Carl Minchew, director of color technology for Benjamin Moore. “Most of them accept the trade-offs because of the lower odor.”

Professional painters also learned to avoid darker colors among the early formulations. Deeper pigments, they say, were, and still may be, more difficult and costly to apply if the contractor or client demands a low- or no-VOC coating.

“Previous generations [of darker pigments with low VOCs] required four coats of a non-flat paint,” says Henri Champagne, a painting contractor in Portland, Ore. “A third of my clients ask for lower VOCs, but they want a quality job first,” requiring him to boost the cost of the job for the extra paint and labor, or seek new-generation coatings that solve the problem.

Cracking the code to create comparable performance to conventional coatings, though, doesn’t come easily or cheaply. “There’s been a fundamental change in the chemistry of paint,” says Minchew. “It’s been a huge, expensive undertaking that will be rolled out over several years,” a process that has proliferated the mainstream paints during the past decade.

To amortize their investments in new formulations, manufacturers are applying the science to other types of coatings they offer. “It’s allowed us to lower VOCs across several lines and business segments,” says Dougherty.

Performance issues have proven to be a tougher nut among so-called natural coatings formulated with milk derivatives, clay, and other mineral-based ingredients. Veteran painting contractor Diane Call of Tucson, Ariz., has tried both milk-based and clay paints with varying success, but sees promising and ongoing improvements among a cottage industry of manufacturers.

“[Clay paints] tend to dry a shade lighter, so it’s hard to judge the final color without a dry sample,” she says, adding that daily surface cleaning (or “scrubability”) also can be problematic.

Work to evolve the model continues, especially in pigment technology that enables deeper, richer colors without adding VOCs back to the coating. Among the big boys, Benjamin Moore, AFM, and PPG have set a higher bar with proprietary, non-VOC colorant systems for new brands of latex coatings, while Green Planet Paints, a clay-based coating maker in Patagonia, Ariz., is reformulating its product to address durability issues and enable a wider range of deeper colors.

Self-Regulation

Despite the efforts of the EPA (created to administer and enforce the Clean Air Act) and other related agencies, regulating VOCs in architectural coatings is a little like Major League Baseball testing for steroids but not human growth hormones. That’s because VOCs are only one category among the toxic chemicals typically found in a can of paint, including those to improve flow, combat bacteria, and defoam the mix, among other benefits.

VOCs also can be added into the base formula after it leaves the factory—sometimes to above regulated levels—by standard color pigments and performance-enhancing supplements, all of which are mostly unchecked. “There are plenty of other chemicals and additives in paints” besides VOCs, says Meredith Aronson, president of Green Planet Paints.

That dynamic, and the evolving definition of what is and is not green, is breeding a caveat emptor approach to the product category. “You need to look at how [various coatings] are made and their overall [environmental] impact, not just their VOC content,” says Aronson.

A paint’s material safety data sheet (MSDS) is a good place to start. In addition to the formula’s VOC content, use the MSDS to check the base paint’s solids or pigment content (the higher the percentage, usually between 25% and 45%, the fewer VOCs), as well as a listing of other toxins (per EPA’s definition) and possible health risks during application and storage.

Also, products registered with the EPA, OSHA, and the Department of Transportation contain toxic chemicals that must be monitored by one or more of those agencies; products that are not registered are not required to be, given their lack of toxins.

As the architectural coatings industry continues to evolve in light of even tighter VOC-emissions standards (see “Regulatory Climate Change,” page 40) and popular demand, builders also should maintain perspective on what is truly sustainable in terms of finishing the walls and ceilings of their new homes.

“Sustainability is also about durability and lasting performance,” says Steve Revnew, director of marketing at Sherwin-Williams. “A coating that lasts five years instead of just one or two probably doesn’t impact the environment all that much more.”

Rich Binsacca is a freelance writer in Boise, Idaho.

Green Planet Paint. This zero-VOC, clay-based, matte-finish coating uses natural mineral and plant-based ingredients to create a lightly washable finish. Depending on surface conditions, the paint covers 350 to 450 square feet per gallon and dries within one hour. Thirty-one premixed colors are available; additional colors are coming for a new line to be launched in late 2008. 520.394.2571. www.greenplanetpaints.com

American Pride. Interior eggshell acrylic latex enamel paint offers a no-VOC formula and contains no other hazardous materials per OSHA regulations. It covers 400 square feet per gallon (one coat) on smooth surfaces and dries to the touch within two hours and up to eight hours before re-coat. It is available in more than 1,200 colors, and is Green Seal certified and qualifies for LEED rating system credits. 888.714.9422. www.americanpridepaint.com

ICI Paints. Freshaire Choice is the first tinted, VOC-free, flat interior latex paint, the company says, thanks to a proprietary colorant system that does not add VOCs. The product covers 300 to 400 square feet (one coat) per gallon and dries to the touch in 30 to 60 minutes. More than 60 colors are available. It is Greenguard certified to qualify for LEED rating system credits; it also is approved under Home Depot’s “Eco Options.” 866.880.0304. www.thefreshairechoice.com

AFM Safecoat. The company’s all-purpose exterior latex satin paint is applicable over a variety of typical surfaces. VOC content is listed as 17 grams/liter, and it is fully tintable using zero-VOC colorants and tints. To maintain low-VOC content, the formulation does not contain mildewcide or fungicide. It covers approximately 350 square feet per gallon (one coat) and dries within one hour. It is the only paint certified by SCS and qualifies for LEED rating system credits. 619.239.0321. www.afmsafecoat.com

Benjamin Moore. Aura interior acrylic paints feature a patent-pending, waterborne colorant system to maintain very low VOC content of 50 grams/liter while delivering deeper and more durable colors, the company says. The paint covers 400 to 450 square feet per gallon (one coat) and dries within one hour; a self-priming quality enables only two-coat applications. The product is certified under Greenguard indoor air quality standards and qualifies for LEED rating system credits. 800.344.0400. www.benjaminmoore.com

Pittsburgh Paints. Pure Performance no-VOC interior coating and primer series maintains expected performance qualities, including hide, color retention, surface mildew resistance, and washability, the maker says. The product covers 350 square feet per gallon (one coat) and dries within one hour. It is available in 1,890 colors using a proprietary tint system to maintain zero VOCs. It is Green Seal Class A certified and qualifies for LEED rating system credits. 800.441.9695. www.pittsburghpaints.com

Sherwin-Williams. The Harmony interior latex coating system is among the company’s GreenSure-designated lines as a no-VOC, silica-free, waterborne formulation. The product purports superior performance qualities, including color retention and durability after repeated washings, as well as anti-microbial properties to protect paint film, says the firm. It covers 350 square feet per gallon (one coat) and dries within one hour. The coating system meets or exceeds Green Seal criteria and qualifies for LEED rating system credits. 800.524.5979. www.sherwin-williams.com

Silacote. Natural, inorganic, silicate-based paint for exterior and interior masonry and similar surfaces is a no-VOC formula that also seals out water, lets the substrate dry passively, and provides no food source for mold. A typical two-coat application covers up to 120 square feet per gallon; it requires 12 hours between applications. The product is GreenSpec listed and qualifies for LEED rating system credits. 800.249.1881. www.silacote.com

Mythic. Mythic paint is a zero-VOC, zero-toxin, noncarcinogenic high-performance paint. The paint production process focuses on improving the latex paint at its core instead of removing toxins from the paint at a later stage, the company says. The paint, which qualifies for LEED rating system credits, is available in 1,232 colors and can be matched to another color through a toxin-free coloring system and using MatchRite color-matching software. 888.714.9422.
www.mythicpaint.com

Bioshield. The company’s natural clay paint contains no VOCs or toxins for low-odor application and drying. It is suitable for various surfaces, painted or unpainted, in low-impact areas; extra protection is advised with the natural wall glaze product. Available in seven standard colors and several custom blends, the paint covers approximately 400 square feet per gallon (one coat), depending on surface conditions, and dries within one hour. 800.621.2591. www.bioshieldpaint.com.

YOLO Colorhouse. Earth’s Color Collection of zero-VOC interior paint offers 53 earth-based colors. Flat, eggshell, semi-gloss, and primer are 100% acrylic with no added solvents for low-odor application and drying. The formula, with 40% volume solids, delivers excellent hide and layout qualities, the firm claims, and it includes a zinc-based microbial additive. The paint covers 400 square feet per gallon (one coat), dries in 40 minutes, and is Green Seal certified and qualifies for LEED rating system credits. 877.493.8275. www.yolocolorhouse.com.