Sustainability
Historic Seattle contends that historic preservation is an effective tool for protecting environmental resources. Because it encourages us to reuse sound older buildings instead of abandoning or demolishing them, and to revitalize existing neighborhoods instead of building sprawling new subdivisions, historic preservation is recycling on a grand scale. The environmental, economic and social benefits of preservation can be further enhanced by improving the energy efficiency of historic buildings. More and more projects in Seattle and elsewhere are demonstrating that older buildings can go green.
As of 2007, the construction, operation and demolition of buildings accounted for 48% the United States’ greenhouse gas emissions. Reusing and retrofitting our existing buildings can reduce these emissions dramatically. Historic preservation can be an important component of any effort to promote sustainable development. The conservation and improvement of our existing built resources, including re-use of historic and older buildings, greening the existing building stock, and reinvestment in older and historic communities, is crucial to combating climate change.
Preservation advocates have long contended that the reuse of existing buildings is one of the highest forms of sustainable design. Until recently, sustainable-design measuring criteria have not allowed much credit toward existing building reuse. Preservation advocates believe the sustainability and preservation communities share common goals and objectives and recommend a reconciliation of their respective interests and objectives to become more integrally linked.
Questions for the design and construction industry that have come from the preservation and sustainability movements include:
How do you balance embodied energy versus energy performance? What about embodied energy in existing materials; the cost of demolition; trucking and land filling debris; and the creation, delivery, and installation of new materials? What is the value of historic buildings and districts in the sustainability equation? Are historic buildings really less efficient than new ones? Did our predecessors have many of the sustainable design concepts figured out long ago? How do you calculate the true cost of rehabilitation versus the true cost of replacing historic buildings? Many historic buildings and districts contain materials and craftsmanship no longer available--should they be thrown away for less durable, manufactured materials? What is the value of the labor intensive skills often needed to work on historic buildings?
The continued use of existing buildings reduces the amount of demolition and construction waste deposited in landfills, lessens unnecessary demand for energy and other natural resources and conserves embodied energy (the amount of energy originally expended to create extant structures).
To address these issues, the U.S. Green Buildings Council recently adopted the LEED-EB ( Leadership in Energy and Environmental Design for Existing Buildings) Rating System. This system helps building owners and operators measure operations, improvements and maintenance on a consistent scale, with the goal of maximizing operational efficiency while minimizing environmental impacts. LEED for Existing Buildings addresses whole-building cleaning and maintenance issues (including chemical use), recycling programs, exterior maintenance programs, and systems upgrades. It can be applied both to existing buildings seeking LEED certification for the first time and to projects previously certified under LEED for New Construction, Schools, or Core & Shell. More information...