When most people think of green buildings they envision slick new buildings such as the National Association of Realtors building near Capitol Hill. Others might imagine more specific features like composting toilets and passive heating which can be found at the Chesapeake Bay Foundation headquarters. However some of the most sustainable green buildings bear few of these more glamorous green building hallmarks (advanced window glazing and shade louvers for example). In many cases the greenest buildings look like a hulking brutalist beast from another era.

Renovation and reuse of existing buildings is one of the most sustainable forms of green building because existing buildings have a tremendous amount of embodied energy from their materials and construction. Consequently it would take many years for the greenest new buildings to save enough energy to equal the energy already contained in an existing building before they begin saving any net energy. Furthermore existing buildings become greener each year they operate because their original embodied energy is used more each day of operation. You can think of it as a law of increasing returns.

The U.S. Green Building Council’s LEED for Existing Building program helps owners of these buildings highlight their positive impacts on the environment. In metro Washington existing buildings located near high quality transit are particularity valuable because they enable reduced automotive commuting. USGBC recognizes the value of these buildings by enabling them acquire more than 2/3 of the points required for basic LEED certification from encouraging employees to use alternative commuting practices.

Location-based certification incentives help ensure that existing buildings are operated and maintained as efficiently as possible by leveraging the marketing value of LEED certification to promote other sustainable practices. Thus if a building is inherently close to attaining certification owners have incentive to pursue additional points by improving the sustainability of a building’s operations. Points are available for almost every aspect of operation and maintenance which means that owners can refine their existing practices to be even more sustainable and receive LEED certification.

In a recent analysis on green building trends in metro Washington LEED for Existing Buildings emerged as the USGBC rating system with the most attributable square feet in the our region between 2003 and 2009. Existing buildings captured 8.6 out of nearly 23 million total square feet (nearly 38 percent). Most significantly Existing Building certifications were pursued without encouragement from local governments. In comparison most other LEED certification systems were influenced by local green building requirements. In other words green building means applying the conservationist adage of Reduce Reuse Recycle to the built environment.

Ryan Hand is an Associate Regional Planner and is also the author of a previous entry on green buildings in metropolitan Washington.