Waterless urinals and recycled carpet could become common building features in the nation’s capital under green construction legislation passed in December by the District of Columbia Council.

The bill, which was signed by Mayor Anthony A. Williams, made the District of Columbia the first major city to require private developers to adhere to the standards of the U.S. Green Building Council. Even before the legislation, the district was already on track to open the nation’s first green-certified stadium.

The bill requires all commercial development of 50,000 square feet or more to meet the building council’s standards starting in 2012. The requirement applies to both new construction and significant renovations of old buildings.

All city-owned commercial projects funded in 2008 or later will have to attain certification, and district-funded housing projects would be required to follow similar environmental standards. The bill also orders the mayor to adopt separate standards for schools—which the green building council is now developing.

“I’m told that it’s the most comprehensive green building legislation in the U.S.,” said D.C. Council member Jim Graham, one of the bill’s sponsors. “It doesn’t rely simply on platitudes; it really does have requirements.”

For the most part, the building council’s standards don’t mandate that a project incorporate specific features. Rather, they award credits in categories such as site selection, energy and water efficiency, and materials. A building must amass a certain number of credits to be certified.

Some in the construction industry have pushed for the use of an alternative rating system that they say is less expensive and easier to use. But proponents of the building council’s system—called Leadership in Energy and Environmental Design, or LEED—say it has built-in flexibility and that the alternative is not stringent enough.

Although the District would be the first major city to require certification for private construction, it would not be the first local government to do so. Pasadena, CA, adopted the standards in March, and Montgomery County, MD, did so last month. Eighteen states and 11 federal agencies use the standards for their projects, said Michelle Moore, a spokeswoman for the D.C.-based green building council.

Environmentally friendly buildings can include simple design elements such as abundant natural light—which can save energy by minimizing the need for artificial light. They can feature windows that open to allow in fresh air, unlike those in most office buildings. Low-air-pollutant-emitting carpet and paint can be used to improve indoor air quality.

Green buildings are likely to be equipped with low-flow water fixtures and even, perhaps, no-flush urinals, which use a chemical trap instead of water, Moore said.

Builders can also earn points by recycling materials. Carpet, for instance, is typically replaced in a building every seven years and lasts 20,000 years in a landfill, Moore said. But it can be recycled by shaving the nylon off the top and reusing the backing, she said.

More than 500 new buildings have been certified under LEED, and developers of more than 3,700 projects have declared their intent to meet the standards, which were first released in 2000. Companies such as Ford Motor Co., Toyota Motor Corp. and Nestle SA have certified facilities, as do Harvard and Duke universities and Boston’s Logan Airport, said Taryn Holowka, a spokeswoman for the building council.

The new stadium for baseball’s Washington Nationals is being built according to the council’s standards and is expected to be the nation’s first certified stadium, she said.

Critics of the D.C. legislation say the council should have allowed developers to choose between using LEED or an alternative system, known as Green Globes that was developed by the Green Building Initiative. But Graham said Green Globes is too permissive.

William Hall, a Washington lawyer who represents building product manufacturers, said it was wrong to give LEED a monopoly on environmental standards. He cited an analysis by D.C. Chief Financial Officer Natwar Gandhi, who concluded that the LEED certification process costs $30,000 per project, while the Green Building Initiative’s process costs only $5,000.

Six states, as well as the U.S. Department of Health and Human Services, recognize Green Globes, which was introduced in the United States only last year, as an acceptable alternative to LEED for their own construction, according to the Green Building Initiative.

Alice Sterling, Pasadena’s green building coordinator, said reaction to the city’s LEED requirements has been positive. She said she is not aware of any project cancellations because of the rules.

“I’ve had some architects actually express delight because they’re able to use their design skills to design sustainable and green buildings,” she said.