As builders and remodelers retool their businesses in a tight credit market, this spring was one the “greenest” yet for the home building industry, the National Association of Home Builders says.

“We’ve said for a while that green building is a bright spot in a down market,” said NAHB Chairman Joe Robson, a home builder and developer in Tulsa, Okla. “However, the growth of the NAHB National Green Building program exceeds even our most optimistic expectations.”

More than 3,100 builders, remodelers, designers and others in the home building business have earned the Certified Green Professional designation. Based on completion of 24 hours of instruction, and industry experience and commitment to continuing education, Robson said the designation provides consumers with confidence in the qualifications of credentialed professionals.

The NAHB will unveil a master green builder-remodeler designation that incorporates additional building science and project management coursework next year, he added.

More than 200 single-family homes, remodeling projects and developments in 43 states have received certification, with another 300-plus scheduled for inspections.

“The NAHB Research Center has certified projects ranging from affordable starter homes to high-end custom homes with every conceivable amenity,” Robson said. “This national certification program clearly is making green building more mainstream.”

The number of state and local homebuilders associations affiliated with the NAHB green program has reached 99. There are now 40 states with affiliated programs. These programs team national certification with professional education and consumer awareness initiatives.

“The fact that 17 of these programs are statewide is especially encouraging for home buyers and home owners because it increases their access to bona fide green building, whether they live in South Dakota or South Carolina,” Robson said.

Homes certified in the NAHB program meet benchmarks set for energy, water and resource efficiency; indoor environmental quality, lot and site development and homeowner education and home maintenance. Green building practices are incorporated into every step of the home building and land development process to minimize environmental impact, NAHB officials say.