“When we build of stone, let us think we build forever.” John Ruskin
Sustainability: “meeting the needs of the present without compromising the ability of future generations to meet their own needs”
World Commission on Environment and Development (Brundtland Report), 1987
Old is the New Green: The 2011 theme for preservation month
Greening Your Old House: A guide to home owners who want to go green
Historic preservation is inherently green—and needs to be greener. That is the core message in two PowerPoint presentations that are now available on the IL SHPO web site. Mike Jackson, FAIA, the former Preservation Services Division Manager has developed these messages about green preservation and presented them to audiences across the state and the country. This conversation about green (a.k.a. sustainable) design and preservation begins with a discussion about the future. Both preservation and green design share a concern about resource conservation and the goal of making a better future. Preservationists begin by identifying places that have enduring value and deserve to be part of the future. Green design begins as a response to the future challenges of resource depletion, population growth and climate change. Preservation has an established set of principles, which have been integrated into contemporary design and construction practices. Green design is developing in much the same way, as a parallel set of values that have to be fit into a market-based construction process. Preservation standards tend to be relatively philosophical, whereas green standards are highly technical and have both prescriptive and performance measures. In preservation community there is a nationally agreed upon set of treatments standards established by the Secretary of the Interior. In the world of green design, there are now of number of rapidly evolving green standards, guidelines, certifications and policies. The role of the “sustainability coordinator” is fast emerging as a new job for someone with the expertise to understand and utilize these competing green design approaches.
The lessons of history
Historic preservationists have a special insight into projections of the future because of our understanding of the past. The past teaches us that our ancestors built structures that used indigenous, renewable materials and produced buildings that responded to local climatic conditions. Historic buildings have many attributes that are now promoted as green design. Operable windows that allow fresh air and daylight, compact building form that is more efficient to build and heat, and cisterns that captured rain water were all common in late 19th century homes. These elements of historic design are now championed as “green.”
Equally green are historic patterns of development. Homes in tight proximity to their neighbors meant that daily life was “pedestrian friendly.” Downtown buildings shoulder to shoulder were very energy efficient. Anyone looking for a planning model of a more sustainable society should look at virtually any city that developed in the era before the automobile. In terms of density and land planning, the city of the 2060s may be more like the city of 1860 than the city of 1960. Preservationists and “smart growth” advocates are both aware of this common value, which is now a part of green planning and design systems. Historic preservationists understand how historic residential neighborhoods and older downtown function from cultural, social, and economic perspectives, and it is quite easy to add an ecological benefit to the discussion.
The tools of green
One of the special challenges to this intersection between preservation and green design has been an examination of the tools that attempt to measure sustainable design. The LEED (Leadership in Energy and Environmental Design) rating system of the United States Green Building Council (USGBC) has become the most common basis for evaluating commercial design in the United States. For residential buildings there are many different green design rating systems. The LEED scorecard does not give much value to building reuse. The underlying roots of this imbalance, and the potential methods of addressing this imbalance have been a focus of the preservation community. The use of Life Cycle Analysis (LCA) to better quantify the value of building reuse is emerging as the building science tool that is needed. The National Trust for Historic Preservation is taking the lead in this research.
Historic property owners with viable and well-maintained buildings are asking a different question. They aren’t asking whether or not they should replace their buildings. Instead, they want to know the best green practices for their structures. Green rating systems developed for new construction don’t work that well for buildings that are not undergoing total makeovers. The continuous improvement of existing buildings is a more appropriate strategy, which can be aided by green guidelines. This is particularly true for historic home owners, who are constantly making maintenance, restoration, and life-style improvements to their homes.
Virtually all models of sustainable design have at their core strong principles of energy conservation and efficiency. The depletion of fossil fuels could be the single greatest challenge of the 21st century. The popular notion that old buildings are “energy hogs” has not proven to be true for commercial buildings. Several recent studies have shown that older commercial buildings can be just as energy efficient as new buildings. The same thing cannot be said for homes. Statistically, pre-WWII homes are one-third to one-half less efficient than new ones. Making historic and older homes more energy efficient is therefore a critical green preservation strategy. How to identify the most cost effective methods to achieve energy efficiency without compromising historic integrity is the essential question. The topics of windows and insulation are particularly important issues that have come to dominate this discussion. Fortunately, new products, technologies and techniques are a being developed to address this challenge. For example, the insulated glass storm window is a new green preservation product that just came onto the market in 2010. High efficiency furnaces and geothermal systems are two examples of “invisible green” technologies. The best practice for “deep energy retrofits” is a growing subject of research that will occupy increasing amounts of preservation discussion in the years to come.
The art and science of sustainability is based upon the three E’s - environment, economy, and equity. Advocates of sustainable design are using these principles to quantify ecologically beneficial building and development practices. The historic preservation movement is well positioned to do the same. Reduce, reuse, recycle has become a mantra of the environmental movement. The preservation movement is true champion of building reuse. This experience has taught us many lessons about the economic, cultural and ecological values of buildings and communities. The historic preservation movement, as a profession and an approach to the treatment of the built environment, is doing something much more important than defining how to save buildings. We are advocates for historic buildings, but we are also building a culture of urban revitalization and building conservation. This may be our most important contribution to the art and science of sustainability.
Mike Jackson, FAIA