WASHINGTON — Washington, D.C. recently took two major steps forward in following the green revolution when it joined a group of cities pledging to counteract global climate change and announced a new set of building codes in the course of a week.
In early December, the nation’s capital became the 58th city to join C40, a network of international cities pledging to lower carbon emissions and increase energy efficiency to combat global climate change. The group was created by former London Mayor Ken Livingstone in 2005 before partnering with the Cities program, a part of the Clinton Climate Initiative, in 2006. New York City Mayor Michael Bloomberg became the chair of C40 in 2010.
As part of the announcement, Washington, D.C. Mayor Vince Gray reported the district had reduced its pollution levels by 12.5 percent since 2006.
A few days later, the city released new local building codes, which included a large expansion to the amount of green requirements for all new construction in the district. The district projects this will result in a 30-percent reduction in the amount of energy used by new structures. This is the first update since 2006, and the new rules will apply to all new or substantially renovated commercial buildings larger than 10,000 square feet, along with multifamily residential structures that are at least four-stories tall.
The changes will place the district on the cutting edge of building regulations, as it based its new rules on the 2012 version of the International Building Code, while most local governments that have made this type of move have only switched to the 2009 standards.
Mayor Vincent Gray said the new codes demonstrated the district’s “strong commitment to being a national and global leader in sustainable building practices.”
The new regulations aim to cut landscaping water use in half and combat the heat island effect, a phenomenon where urban areas with small amounts of green space experience a higher temperature than less developed areas. This occurs because concrete, pavement and other building materials absorb heat at a higher rate than green spaces with trees or other plant matter. It can be counteracted with living roofs, which are populated with plants that provide added insulation without absorbing as much heat from the sun, or by using shade or reflective roof materials that counteract heat absorption.
The list of new green requirements is robust to say the least. Changes were also made to some safety codes, such as a rule mandating all new residential units to include smoke and carbon monoxide alarms in or directly next to all bedrooms.