Pocketbook concerns have merged with environmental interests in recent years, with homeowners and buyers focusing on green building with new enthusiasm. For decades, environmentally aware architects, builders and consumers have touted the benefits of solar power, careful land use, recycling and using less energy, along with the cost-saving payback of such efforts.

Since 2003, the number of counties with green building programs has risen from eight to 39, according to an American Institute of Architects (AIA) study titled, "Local Leaders in Sustainability: Green Counties." The study found that the eastern region of the country, which includes the Washington area, has the most counties with green building programs, with 19 programs covering a population of about 19 million people.

The study focuses on Montgomery County as one example of an innovative program that has encouraged the development of sustainable buildings. The Arlington County government introduced the Green Home Choice Program in 2003 as incentive for builders to go green. The program includes listings of the techniques and products that make homes more environmentally friendly.

The District was named one of the Top Ten Best U.S. Green Roof Cities by the advocacy group Green Roofs for Healthy Cities. Todd Tibbitts, senior vice president for property services at Post Properties Inc., wrote in an article on green roofs for Units magazine that in 2007, more than 55,000 square feet of new green roofs were installed in the District.

Green roofs, which can be installed on residential and commercial buildings, feature landscaping and foliage on the top of the building that often can be used by residents and tenants as a natural space for relaxing and socializing. Green roofs limit water runoff, shield the rooftop from damaging ultraviolet rays and provide extra insulation that minimizes cooling costs and cuts down noise pollution. A green roof can add to the life span of a roof, in some cases doubling the length of time the roof can function.