Imagine Homes doesn't build houses like they once were built. But this doesn't mean the company is forsaking the traditional home construction ideals of care and craftsmanship. It just means Imagine is building homes with an eye toward site sensitivity, energy and water efficiency, and indoor air quality.

"We saw a need in [our] marketplace," says John Friesenhahn, president of the recently launched San Antonio-based builder. "[Customers] were asking for homes that they could afford but that didn't have a cookie-cutter feel and also that wouldn't ruin our area's beautiful natural habitat. We thought, 'Well, if we don't start building architecturally classic homes that have less impact on the environment, then what is San Antonio going to look like when our kids are grown?'"

Into Its Own
By any standard of measurement, green building is hot. As oil hovers around $70 a barrel, interest in conservation and energy efficiency has come to dominate the consciousness of the average American consumer. The subject even has its own exhibit at the National Building Museum in Washington, D.C., "The Green House: New Directions in Sustainable Architecture and Design," which will close in June and then travel to other cities.

For years the purview of the Birkenstock-wearing hippie fringe that built homes with straw bale, rammed earth, and recycled building products, green building has become an integral part of commercial, public, and civic construction. Businesses, governments, and educational institutions are seeking to create buildings that use less energy and are healthier for human habitation.

According to the NAHB, 14,600 green homes were built in 2004, up from 2,500 in 2000. In addition to state and local green building programs that have cropped up over the years, builders can certify their homes through voluntary national programs such as the U.S. Green Building Council's Leadership in Energy and Environmental Design (LEED) or Masco Contractor Services' Environments for Living program. They also can build green using the NAHB's Green Home Building Guidelines or the EPA's Energy Star program. These programs offer guidelines on how builders can improve their homes' site development, energy efficiency, and overall sustainability.

Despite its increasing popularity, however, green building remains a complicated topic that often leaves builders scratching their heads. What exactly is green building? What does building a green house entail? What does it cost to build green? And what are the minimum features a house must have before it can be considered green?