McGraw-Hill Construction presented the findings of its latest market research investigating "green" home building, focusing on changes in green building activity between 2001 and 2007; the impact of the down market on green home building; opinions and preferences of builders for green materials and processes, and triggers and obstacles affecting green building expansion.

The major findings of the survey, which is co-sponsored by the National Association of Home Builders (NAHB), include:

• The residential green building market is expected to be worth $12 billion to $20 billion (6% to 10% of the market) this year.
• In five years (2012), the market is expected to double to 12% to 20% market share, or $40 billion to $70 billion.
• 40% of builders think green building helps them market their homes in a down market.
• Quality has emerged in this down market as the most important reason for building green. Previously, builders were motivated by energy cost savings of green homes and doing the right thing, which still came in #2 this year. This is likely due to green home marketing and how it improves quality of life.

"We have hit the tipping point for builders going green," said Harvey M. Bernstein, McGraw-Hill Construction vice president of Industry Analytics, Alliances and Strategic Initiatives. "This year, the number of builders who are moderately green -- those with 30% green projects -- has surpassed those with a low share of green -- those who are green in less than 15% of their projects. Next year, we will see even greater growth, with highly green builders -- those with 60% green projects -- surpassing those with a low share of green. This year has seen an 8% jump over last year, and we expect another 10% increase next year."

"It's official. Green has gone mainstream," said Ray Tonjes, chair of the Green Building Subcommittee for NAHB. "And now, the NAHB National Green Building Program is making it easier for home builders to provide sustainable, environmentally friendly homes for their customers. We're ready for the market transformation that McGraw-Hill Construction estimates."