Architecture for Better Future

by Bob Falk and Brad Guy



Depending on your generation, you may have been taught: "Waste not, want not." Thrift is certainly one incentive for deconstructing buildings for reuse. In addition, many of us are motivated by a desire to be environmentally sensitive, a fondness for antiques and other items from the past, a yearning to have more control over the quality of materials used in construction, or a recognition that many of the materials available for salvage are of higher quality than those produced today.

As with many environmentally conscious activities, deconstruction and building-material reuse offer a direct and measurable way to reduce one's negative effect on the planet. Building construction, use, and maintenance make up a resource-intensive business.

In the United States, the construction, use, maintenance, and disposal of houses are responsible for nearly a half of the country's energy use. According to the U.S. Geological Survey, about 60 percent of all material (except food and fuel) used in the economy each year is consumed by the construction industry.

There are many opportunities to reclaim and reuse building materials. In 1996, the U.S. Environmental Protection Agency (EPA) estimated that the equivalent of 250,000 single-family homes are disposed of each year. This represents an estimated 1 billion-plus board feet (2.4 million cubic meters) of available salvageable structural lumber, or about 3 percent of our annual softwood timber harvest.

Reusing this lumber could save 4,250,000 trees on 150,000 acres (61,000 hectares) of timberland every year. The amount of recoverable materials is even greater if you add nonstructural building products, such as the millions of windows, doors, and fixtures and the thousands of miles of trim work, siding, and flooring available.

Not only does unbuilding (and the reuse of building materials) save resources but it can also yield higher-quality materials than are available today. Much of the salvaged lumber available through deconstruction is from the decades of old-growth harvesting — so the wood is higher in density and has fewer defects — which represents a resource largely unavailable today.

In old factories, silos, and water tanks you can find high-quality heart pine, redwood, and fir timbers; in old barns, pine, chestnut, and oak; and in older school bleachers and benches, quality maple and fir. Factories, farms, and industrial buildings aren't the only sources of such materials; high-quality wood can also be found in millions of older houses.

In nearly every community, wood flooring, windows, doors, cabinets, and lumber can be salvaged. If you keep your eyes open, high-quality architectural materials, including hardware, period lighting, elaborate bracketry, and trim are also readily available.

Not an Alternative to Preservation

We hope you consider deconstruction only when building preservation or adaptation is not an option. Most buildings are not historically significant; however, it's best if you determine that before deconstruction. Historic preservation typically is invoked only to protect a significant historic, archaeological, or cultural resource.

We suggest that when preservation of the whole structure is not possible, unbuilding can at least serve as "preservation in pieces" to recover significant construction materials and design features. In some cases, a building shell or only the street front will be retained to preserve historic building character in a community, while the rest is removed to allow for a modern interior.

Given the selective nature of these projects and the care needed to avoid damaging the parts that might remain, unbuilding is a viable solution. In these situations, the original materials can often be directly incorporated in the preserved building.

Unbuilding is a good step in preserving resources and avoiding waste; it is directly in line with the tenets of "green building." A simple raised wood-floor, wood-framed older house can weigh 50 pounds per square foot (244 kilogram per square meter). A 1,500-square-foot (140-square-meter) light wood-frame building can therefore weigh more than 37 tons (34 metric tons) or the volume of about three 40-cubic-yard (31-cubic meter) container loads.

In addition to these raw materials of the building, there are also the original materials consumed to make the finished building materials and the energy and pollution resulting from extraction, processing, and transportation at different stages of manufacture.

The waste itself becomes a burden in the landfill, consuming land and potentially leaching into soils and groundwater. By deconstructing, you are also doing your neighbors the very simple favor of extending the life of your local landfill.

The United States is one of the most consumptive nations on the planet. According to John Ryan and Alan Durning's book, Stuff: The Secret Lives of Everyday Things, the average American consumes about 120 pounds (54 kilograms) of natural resources each day. With only about 5 percent of the world's population, the United States consumes about 24 percent of the world's energy. Unbuilding can help decrease this percentage through the direct reuse of building products.

With a greater realization of the positive effects of greener building practices, the use of recovered materials is typically rewarded in the many green building certification programs that have appeared in recent years.

Organizations such as the U.S. Green Building Council, the National Association of Home Builders, and the National Association of the Remodeling Industry have all developed green programs for use by the commercial and the residential building markets.

A green-building certification provides not only a perception of quality but also real energy savings and increased value on a new or renovation project over the long term. More and more municipalities are considering policies and ordinances requiring building deconstruction to be considered along with traditional demolition and disposal.

Reuse vs. Recycling

The "three Rs" of waste reduction are, in order of priority: reduce, reuse, recycle. This hierarchy suggests that to be as environmentally benign as possible we should first reduce our level of material use, then reuse as many materials as possible, and finally recycle what can't be reused.

Unbuilding focuses on the reuse and recycling portion of the three Rs, and it's important to make a distinction between these activities. Reuse is the heart of the deconstruction effort, by which the primary focus is to maintain the material or component in its original form. This might include some cleaning, removal, or replacement of some part.

The intent is to move these salvaged building materials directly back into new construction or remodeling: a used door in place of a new door, a used window instead of a new window, a salvaged joist rather than a new one, and so on. Or the salvaged materials can be used in a new way: a used door becomes a wall panel, a window serves as a cabinet front, or the floor joist is now a wall stud.

Recycling, on the other hand, is a more indirect use of materials and typically involves changing the form of the material for use as an entirely new material. For example, we wouldn't reuse a concrete pillar from an old building in a new building. It's not practical. However, it is very practical to break up that pillar and recycle the concrete and steel rebar into other uses, such as in roadbeds and new cars, respectively.

Unbuilding and its associated reuse are very well suited to wood-framed construction, where most materials can be reused. Demolition and its associated emphasis on recycling are well suited to concrete and steel construction, whose materials are difficult or impossible to directly reuse, and breaking down these materials is an inherent part of the recycling process.

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