Using Wood for Responsible, Renewable Building

Photo: emory.edu

More than 90 percent of the homes in North America are constructed of wood — and for good reason. Wood is plentiful, durable, beautiful, and renewable. In fact, it’s the only building material that renews itself. At a time when common sense and solid environmental values are asking homebuilders and remodelers to make educated decisions about the materials they use, wood continues to be an environmentally friendly choice.

Using Wood for Healthy Forests and Communities 
Our landscape is very different from a century ago when farming was encouraged and widespread clearing of the land took place throughout North America. Today, the United States has recovered so much forestland that it has nearly the same amount as it did in 1900, even though the population has increased by 143 percent.

With one third of the U.S. covered by forests, it’s important to note that over 200 million acres in North America overall are independently certified as sustainable and responsibly managed. Together, the U.S. and Canada maintain the largest area of protected forestland in the world.

No farsighted logger or forester wants to see the woods and forests disappear. It is in the best interests of forest product companies—long-term suppliers of products ranging from two-by-four lumber to paper to mulch — to keep their forest and ecosystems healthy. Doing so keeps their businesses robust.

Industry initiatives, local, state, and federal regulations, and a good dose of public awareness have led to a better balance between commerce, community, and the environment. The use of wood building products is beneficial to the advancement of modern forest management practices. Demand for forest products creates a similar demand for sound forestry practices, assuring that the natural resources continue to be sourced from well-managed land.

Builders and homebuyers want wood inside and outside their homes. As a result, many programs have been developed to encourage the responsible management of our natural resources. “Certification is a way to recognize these companies for what they already do well, and give them the recognition they deserve,” says John Landis, Technical Specialist for SmartWood, an international wood stewardship firm based in Richmond, VT. As these programs expand, consumers can be further assured that the wood they use comes from forests that are sustainably managed and support the communities that surround them.

How To Build Responsibly
All builders and remodelers should begin to assess building materials for their impact on the environment. The energy efficiency of a completed structure is just one of the criteria used today. It is also important to assess the total environmental impact of the components within the building. First look at how materials are manufactured, where they are made, how long they will last, how they will be recycled or renewed, and how much fossil fuel will be used to produce, install, or dispose of those materials. Only then can builders and buyers understand the total impact of building choices on the environment.

Studies and models like the Athena Life Cycle Assessment show that wood is by far the superior choice for building in all categories: total energy use to build, occupy, and dispose of; air and water emissions produced during manufacturing; solid waste generated in production and recovery; greenhouse gases produced during manufacturing; and ecological resource use. The model, developed by the Athena Sustainable Materials Institute for use by architects, builders, planners, and consumers, compares wood with steel and concrete for environmental impact.

Patrick Moore, a Greenpeace founder and now founder and chief scientist of the organization Greenspirit, is quick to point out that steel is manufactured in a plant, while trees are manufactured by nature. Trees come from nature and return there when their life of service is complete.

Many areas even offer recovered-wood programs, where wood retrieved from demolition sites and abandoned structures is sold for reuse. Many hardwood mantles, trims, railings, and doors are restored and reused daily. Even basic framing timbers can be recaptured and reused. “Whenever you buy wood, you send a signal to the forest to grow another tree,” says Moore. When that tree is responsibly grown and harvested, using wood helps regenerate forests and create living habitats, places of beauty, and recreation areas for all of us to enjoy.

Where Wood Is Used
A quick house tour will showcase wood’s ever-present place in daily life. Wood-framed homes are by far the most common construction in America today. Spruce, pine, or fir may be used. “Typically it’s spruce,” says Mike Gervais, president of Prime Construction in Burlington, VT. “Pine is usually saved for interior and exterior trims. It’s straighter grained and better quality,” he says.

Pine and cedar are also popular for exterior siding—clapboards, shakes, and shingles. “But with trim we also have other options like finger-jointed trim and culled wood products,” Gervais says. These are engineered lumber solutions that recover wood scraps and bind them in an epoxy or resin solution to create superior-strength, dimensionally stable framing and trim pieces.

Hardwoods like maple, cherry, and oak are typically used for high-profile applications like floors, trim, cabinetry, and furniture. Mahogany, cedar, and ironwood are popular choices for decks. Exterior doors are frequently made of hardwood and finished to bring out the rich grain and color of the wood.

Wood Makes Sense
Wood is still the dominant choice for trim because it is easily milled, profiled, and installed. Wood can be shaped, sanded, painted, or stained, making it an extremely versatile building product. Wood is easily repaired or replaced. Dings, nicks, and dents can be sanded and refinished. Trim can be changed. Even the house itself is easily expanded or altered when wood framing is used.

Other materials, such as concrete, are far less forgiving and require significant demolition and corresponding expense should the homeowner wish to change the shape, structure, or existing openings in the home.

Zero Waste
Besides being adaptable, wood is a practical building material. Mills make wise use of wood, for both economic and environmental reasons. Nearly the entire tree is used. Bark is removed and used for mulch and decorative landscaping. First cuts and unusable board feet are recovered or culled for use in engineered wood products. Board ends are cut up and sold as hobby wood. Sawdust and shavings are packaged for animal bedding. In some mills, scrap wood is even used to produce energy or steam to keep the mill and kilns running.

“All these lumber companies are looking at ways to have zero waste,” Gervais explains. Whether it’s low-waste mill management, engineered lumber solutions, culled wood programs, or scrap recovery, economical use of timber and all of its products makes sense in today’s world.