New rating systems for green houses draw both interest and conflicts
By Ted Smalley Bowen

The Cannon Beach Cottage in Oregon, designed by architect Nathan Good, was given a “green project of the year” award by NAHB. Photography: Courtesy Nathan Good

New rating systems for green homes have underscored the steady buzz about green building within the design and construction community, as well as the desire of industry groups to exert more influence on how green building is defined. In January 2005, the National Association of Home Builders (NAHB) launched its Model Green Home Building Guidelines, a template for voluntary, self-administered rating systems. Meanwhile, the U.S. Green Building Council’s (USGBC) long-awaited LEED for Homes specification is slated for pilot testing in mid-2005.

The two systems have been developed with different markets in mind. NAHB’s guidelines are geared toward mainstream builders. The Green Building Initiative, a nonprofit organization formed by the Wood Promotion Network and other industry groups with ties to residential construction, will work with local builders’ associations to adapt these guidelines to local markets, according to participants. In contrast, LEED for Homes is a national rating system intended for designers, like the other LEED rating systems. Officials predict the latter will be used mostly for high-end residential construction as well as affordable multifamily housing, unlike the mainstream builders targeted by NAHB. Nevertheless, this group’s new guidelines have been perceived by many as a preemptive response to the more stringent LEED system.

The NAHB guidelines assign points to projects for energy efficiency, recycling, water conservation, indoor air quality, reducing the use of pesticides and other household chemicals, and limiting high-maintenance lawns. It also encourages a holistic approach to designing green homes—one that emphasizes environmental issues from the start; considers the interdependencies of building systems; and stresses durable, low-maintenance materials. Green building “is growing exponentially, and NAHB didn’t want to be caught in the undertow,” says John Loyer, construction codes and standards specialist for NAHB. “We anticipate some degree of legislation and code enforcement, and we wanted to offer not a standard, but a voluntary guideline that could be used by builders who want to green their construction practices.” In March, the group sponsored its first green building conference in Atlanta and gave awards to several projects (all of which preceded the release of the guidelines).

The NAHB template was drawn up with input from a committee of industry representatives, builders, architects, and government and environmental groups. For the most part, local builders’ associations will handle certification, says Loyer. The template’s point system and gold, silver, and bronze awards bear passing resemblance to LEED.

Perkins Eastman Architects completed a green remodeling of a convent in Pittsburgh. Photography: © Denmarsh Photography

According to a preliminary LEED for Homes checklist, baseline requirements include certification under the Department of Energy’s Energy Star program, a soil and erosion control plan for construction sites, a basic water-management plan, third-party verified room air flow rates, and standards for the building envelope and indoor environment. It also prohibits the use of tropical hardwoods; sets limits for landfilling of construction wastes; and requires a materials durability plan, while giving a significant incentive for location within developments that meet the LEED for Neighborhood Developments standards, due out later this year. The latter, a collaborative effort between the USGBC, the Congress for the New Urbanism, and the Natural Resources Defense Council, combines green-building and smart-growth principles.

The NAHB and USGBC developed their ratings independently, although there was communication between the organizations, according to officials. Yet, while acknowledging the USGBC’s stated goal of greening the construction industry, Loyer says LEED for Homes “is not something we’ll be recommending to our members.”

The primary difference between the LEED for Homes specification and the NAHB guidelines is the national scope of the former, according to LEED for Homes program director Jim Hackler. “There are more than 40 green-building organizations in the U.S.,” he says. “There’s interest in LEED from government agencies and production home builders. They’re looking for national consistency.” While the distribution of LEED for Homes might be decentralized due to the nature of home construction, the quality control, testing, and rating will remain consistent, according to Hackler. One criticism of the standard, that it fails to consider regional differences in climate, materials, and other variables, may prompt changes in later versions of the standard, he adds.

Who should define green?

EDG Architects involved future residents in the design of their building, the Eastern Village Cohousing Condominiums in Silver Spring, Maryland. Photography: © Tom Kochel

Over the past five years, LEED has taken root at the federal, state, and local levels, mostly through design standards for public projects, and it shows signs of migrating to building codes as well. But in recent months, the NAHB and an industry consortium, the North American Coalition on Green Building, have been critical of the USGBC’s standards- setting processes, opposing legislative and regulatory enforcement of sustainability measures. The coalition was established in 2003 by General Electric and trade groups representing manufacturers, forestry and wood-products companies, chemical companies, vinyl producers, and others dissatisfied with USGBC, which doesn’t extend membership to trade groups. The coalition contends that this policy limits the influence of individual companies (though some coalition member companies are also USGBC members) and undercuts their claims of a consensus-based process, says Jerry Schwartz, the group’s cochair. Schwartz, however, did credit USGBC’s recent decision to use life-cycle analysis when hashing out standards. “It’s a step in the right direction. They did a great job of reaching out to trade groups,” he says.

USGBC president and C.E.O. Rick Fedrizzi counters, “We feel our broad-based membership has done an extraordinary job of achieving a consensus-based platform for action. The only way everyone can profit is through open and vigorous dialogue, but we also know we must not let dialogue substitute for progress.”

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