Citizens for
Glen Ellyn Preservation |
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Preservation = Conservation
The greenest building is the one already built.*
As the national focus shifts to global warming and energy conservation, preservationists and environmentalists have found their concerns to be remarkably similar. Related problems of pollution, urban/suburban sprawl, fuel consumption, and full landfills have emphasized the need for sustainability in terms of the built environment. A significant part of the problem is that the modern teardown trend has had a much greater impact on our well-being than just the loss of historic architecture and greenspace. In Glen Ellyn alone there have been 635 residential teardowns since 1993. Given that the demolition of one 2000 square foot bungalow generates about 120 tons of waste; our village has added at least 76,200 tons of this type of waste to the environment, some of it toxic, such as lead paint dust and asbestos. In addition, a 5,000 square foot replacement home generates an average of 10 tons of construction waste, bringing the total to 130 tons (260,000 pounds) from just one project. It is estimated that in Glen Ellyn approximately 60% of the total waste going into our dumps each year is from demolition. While the average homeowner is making the effort to reduce, reuse and recycle, for the most part, the building industry is not. |
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Our built environment has a considerable impact on both the use of our national resources and on the quality of our air and water. Based on figures from the U.S. Energy Information Administration, our nation’s buildings generate:
40% of total energy consumption
72% of electricity consumption
30% of greenhouse gases
39% of carbon dioxide emissions
Given these figures, one might assume that replacing older, historic structures could be beneficial, in light of advancements in engineering, heating, cooling, etc. However, the common perception that older structures are energy inefficient turns out to be a myth. In fact, current data provides proof that older buildings can be equal in energy efficiency to new ones. With features such as large, operable windows placed cross-wise for ventilation, high ceilings, deep porches and thick, breathable plaster walls, older buildings are both inherently efficient and healthful in design. Built to endure the test of time, they were constructed with old-growth wood that, because of its density and natural oils, can last for centuries, genuine examples of sustainability. By contrast, new fast-growth woods may suffer from rot within only a couple decades, particularly on exteriors or in damp environments.
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682 Hillside, Glen Ellyn
The top image is of the home that existed before the teardown.
The bottom image is the structure built in it's place. The historic
pre-settlement oaks in the photo have all since died due to
construction damage. |
Through projects such as weatherstripping and caulking original windows and doors, and adding storm windows, attic insulation and modern heating and appliances, older homes can be brought up to current standards while satisfying the needs of contemporary life at far less expense than reconstruction. These basic improvements can reduce energy consumption by as much as 25%.
Typically, older homes were built of local materials that did not require long distance hauling, which adds to the energy expenditure of construction. Actually, this is an important part of what is known as embodied energy, that is, the full measure of energy expended in the harvest, manufacture, and transportation of materials, as well as the energy that was used during the construction process of each standing building. Therefore, the full measure of energy use in new construction includes the embodied energy lost in the demolition of the structure that it replaces. According to Mike Jackson, chief architect of the Illinois Historic Preservation Agency, even with the most energy-efficient type of construction, if it includes the demolition of an older structure, a new residential building may not begin saving energy for close to 28 years, and energy payback for a commercial building may not start for over 60 years.
Quite the reverse, green retrofitting of historic buildings begins immediate payback to both the environment and the pocketbook with the additional benefit of preserving the character of our communities. This makes preservation the very essence of conservation.
Sources:
www.nationaltrust.org/issues/sustainability/
www.sierraclub.org/sprawl/report99/community.asp
www.eia.doe.gov/consumption/index.html
www.thegreenestbuilding.org/
www.yourhome.gov.au/technical/fs31.htm
www.glenellyn.org
*quote by architect Carl Elefante in 2007 Forum Journal, publ: National Trust
Embodied Energy Computation
Embodied energy is the sum of all of the energy used to build a house, from acquiring, manufacturing and transporting building materials to the energy needed for the actual construction process. Below is the resulting energy cost to build a new home from an imagined teardown of a typical bungalow. |
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1917 Craftsman Bungalow -
342 Montclair (left): 2,601 square feet
lot: 14,353 square feet
embodied energy: 18,207,000 BTUs
(equal to 15,832 gallons of gasoline)
2008 New Construction -
6,459 square feet allowable for this lot
embodied energy: 4,521,300,000 BTUs
PLUS embodied energy of former house:
18,207,000 BTUs
PLUS demolition energy: 8,063,100 BTUs
TOTAL 6,350,063,100 BTUs |
The total energy to demolish the existing home and build a new house is equal to 55,218 gallons of gasoline, which, at $3.40 per gallon, would cost $187,741.20. Since the average car now uses about 20 gallons per week, this could provide enough fuel for 53 years.
For an online calculator to find your home's embodied energy, visit www.thegreenestbuilding.org.
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