As the green building industry’s focus has shifted toward adaptive reuse and retrofitting the existing building stock, the debate about balancing retrofit needs with historic preservation guidelines has moved to the forefront.
In our current work developing an Energy Efficiency & Conservation Strategy with the City of Ellensburg, this issue is salient. Ellensburg has a historic downtown with an active historic preservation interest group, but this real estate is significantly underutilized. Although street level spaces in the downtown are mostly maintained and leased, upper stories are virtually abandoned. Retrofits could improve energy performance and make these spaces more desirable for tenants who now look for space in modern developments outside of the City core. At the mere mention of revising building codes to allow for incorporation of renewables on existing buildings, however, a protest arose at the thought of installing PV panels on historic buildings.
So do we touch historic buildings to make them more efficient? What can we do, and how do we best balance historic preservation needs with adaptive reuse and energy efficiency goals? These questions have been on my mind for several months now. During a recent trip to The Netherlands, Germany, and Austria, I kept my eyes open to see how these countries are addressing this issue. There’s a visible juxtaposition of old rural villages and brand new renewable energy technology in much of the countryside(s) I visited. In The Netherlands, old wooden windmills sit next to sleek new wind farms and historic straw roof farms have incorporated on-site solar. In Germany, PV blankets the roofs of old barns and farms, and Germany’s solar incentive program has been so successful that the government has had to place it on hold to catch up with demand. In Austria, the roofs of many farms and inns in the 1,000 year old village of Soelden are dotted with solar hot water and PV panels. In my opinion, there is a true beauty in this mix of old and new. Not to mention efficiency and excitement for the future.
Adaptive Reuse is conventionally defined as the process of adapting old structures for new purposes. Much of the debate surrounding adaptive reuse pertains to whether it makes sense to keep the building and retrofit it, or tear down and build new, but that’s another issue that we’ll explore in a future article. New buildings are now designed with rigid and strong exteriors, yet flexible floor plans interiors making adaptive reuse in the future more likely.
Historic Preservation is part of a national movement to protect buildings that are least 50 years old and are associated with, or significant for, historic people or events, architecture, craftsmanship, or design; or are valuable for historical research. At the federal level, the National Park Service (NPS), part of the U.S. Department of the Interior, oversees the National Register of Historic Places which is an official federal list of districts, sites, structures, buildings, and objects that are deemed worthy of preservation. It’s important to know that the National Register is primarily a tool to recognize historic properties - it does not mandate how they must be treated. A listing thus helps to protect a property but it does not restrict property owners. This is where the state and City regulations come in: they can add restrictions to a listed property, and they do this through State Historic Preservation Offices (“shippoes”). Shippoes were federally mandated to carry out provisions of the Act of 1966 and their role is to locate and record historic resources, nominating these resources to the National Register, and providing technical assistance and consultation. There are also some State Historic Registers (Washington State has one: the Dept of Archeology & Historic Preservation) as well as municipal programs that recognize local historic sites or districts, and these come with their own sets of regulations that often go beyond federal regulation in restricting what private property owners can do.
When sustainability planners ponder adaptive reuse, both on old buildings and those on the historic register, the issue of embodied energy comes up. According to the Advisory Council on Historic Preservation, about 80 billion BTUs of energy are embodied in a typical 50,000-square-foot commercial building. That’s equivalent to 640,000 gallons of gasoline, which is wasted if you tear the building down. On top of that, demolishing that same 50,000-square-foot building creates about 4,000 tons of waste. Construction of the replacement building will take additional energy in construction, natural resources, greenhouse gas emissions, and waste. Preservation Green Lab (see resources) is conducting a study that will provide more information on this topic, and we’ll report on this study in the near future.
According to Patrice Frey’s research for “Building Reuse: Finding a Place on American Climate Policy Agendas,” Older buildings can actually be remarkably energy efficient because of their quality of construction, their downtown or central locations, and their use of passive heating and cooling methods. When the GSA examined its buildings inventory in 1999, it found that utility costs for historic buildings were 27% less than for more modern buildings. We need to hold on to buildings that are well designed, that meaningfully link us to our past, and that have plenty of good use left in them.
When considering adapting historic buildings with a sustainable design, consider these key factors:
- Don’t break the rules. Bottom line, there are standards you must follow outlined in the Secretary of the Interior’s Standards for Rehabilitation. The standards seem rigid, but there’s significant flexibility as long as you are consistent with the character of the building. Consider it a “design challenge.”
- Lengthen your planning horizon. This applies whether you are adapting or constructing new, but after a trip to Europe this is at the top of my mind.
- Be passive. Old buildings relied on passive strategies. Maintaining a passive approach will save money, keep renovations simpler, and make O&M easier.
- Embodied energy. We’ve already touched on this. We’ll discuss the science behind this in our next post on this topic.
- Verify operating energy. In doing energy modeling of an existing building, you might find it’s better than you thought it would be. Don’t assume it’s an energy hog because it’s old.
- Work with your local preservationists. It’s best to develop an overarching strategy to your project, to determine what’s sacred, and what’s open to change. And provide opportunities to learn how historic buildings and sustainability goals overlap.
- Don’t make assumptions about windows. There may be other ways to amp up a building’s energy efficiency. In the ongoing renovations of the historic Empire State Building the developers took the creative path of upgrading the existing windows rather than replacing them. Floor by floor they are removing windows, “re-manufacturing” them on-site using local labor (meaning more green jobs!) The result are windows that test to R-8 and “fit.”
- Take advantage of resources. See below .
- Preservation Green Lab: National Trust for Historic Preservation.
- The Sustainability Initiative, National Trust for Historic Preservation.
- The American Institute of Architects Historic Resources Committee.
- The Association for Preservation Technology
- International Federal Historic Preservation Tax Incentives
- The National Park Service Technical Preservation Services.
- Historic Preservation and Green Building: A Lasting Relationship Feature - Environmental Building News January 2007.
- Building Reuse: Finding a Place on American Climate Policy Agendas. Patrice Frey, Paul Anderson, Monica Andrews, and Carl Wolf. National Trust for Historic Preservation.
Yvonne Kraus, LEED AP and CSBA and Senior Project Associate for O'Brien & Company, Inc. specializes in green building program development, community and corporate sustainability strategies, and LEED for Existing Buildings: O&M. She is the Project Manager for the City of Ellensburg’s Energy Efficiency & Conservation Strategy (EECS), and led the development of the Economic Sustainability Strategy for the City of Kirkland (adopted), and of the Sustainability Strategy for the City of Sammamish (under consideration for adoption). The photo of Ellensburg's downtown was taken by Bob Bengford of Makers Architecture, leading a Land Development Code Update for the City concurrent to and integrated with the EECS project.
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