Wood: The Sustainable Choice for Green Building
- No other material can match wood’s unique combination of benefits, including strength, affordability, ease of use and environmental superiority.
- Wood-frame construction has a 100-year track record for safety and dependability. That’s why nine out of 10 homes today are built with wood.
- Building codes require all materials to provide the same degree of protection, even for extreme events such as earthquakes and hurricanes. Wood-frame construction is as safe, sturdy and dependable a building material as any other.
- Wood is the best insulator against heat and cold, which makes it the most energy-efficient material that can help keep home energy bills in check. Unlike steel and concrete, wood doesn’t conduct heat and cold. Wood is 400 times less heat conductive than steel, so homes built with wood studs take less energy to heat and cool.
- Wood is the most affordable building material. The economy of wood construction is one of the many reasons why wood-frame construction has remained the preferred method for residential construction.
- Wood is easy to use and widely available. Its practicality and workability make construction simple and efficient for use in residential or commercial applications, including multi-story projects.
- As the world’s only renewable building material, wood can not only be recycled, but regenerated as well. What’s more, trees provide benefits to the environment while they grow, taking in carbon dioxide and releasing oxygen.
- Wood contributes far fewer greenhouse gas emissions than its non-renewable counterparts, steel and concrete. Although wood products make up 47 percent of all raw materials made in the United States, its share of energy consumption during production is only four percent of all manufactured materials.
The Environmentally Friendly Choice
Wood may be the most environmentally friendly material available for building homes or businesses. Here’s why.
- Wood products are produced from trees, a naturally renewable resource. More wood is grown each year in the United States than is harvested.
- Waste is virtually eliminated when trees are used to make wood products. Bark, trims and sawdust are used as an energy source to help power wood production facilities. It takes far less energy and fossil fuel to produce wood products than to manufacture concrete and steel.
- The durability of wood products contributes to the long life of a home. Wood products also store carbon, reducing the amount of carbon in the atmosphere.
- At the end of their initial service life, wood products are easily recycled for other uses. Wood contributes fewer greenhouse gas emissions than non-renewable steel and concrete.
- Study after study in Europe, North America and elsewhere has shown that wood outperforms other products when considered over its complete life cycle. One study, conducted by the Consortium for Research on Renewable Industrial Materials (CORRIM) compared the environmental impacts of homes framed with wood and steel in Minneapolis and with wood and concrete in Atlanta – the framing types most common to each city. According to the report, the homes framed in steel and concrete would require 17 and 16 percent more energy respectively (from extraction through maintenance) than their wood framed counterparts.*
Enhancing the Environment
Suppose America stopped harvesting its trees to make lumber, plywood, paper, and other wood products. What effect would this have on our environment? Let’s consider.
What would we use as a building material for homes and furniture, or paper for books and stationery? Would we substitute steel, aluminum, masonry, plastic, and other products? Buy wood from other countries? Or do without?
If we substituted non-wood building products, the environment would be the clear loser. Non-wood products are environmentally expensive. The supplies of ores and petroleum for their production are finite; once gone, they are gone forever. Wood, on the other hand, is a renewable resource from an endless supply of trees. Non-wood products require far more energy to manufacture than wood: nine times as much to make a steel stud as a wood stud, for example. That further depletes finite supplies of fossil fuels and coal. Not to mention greater pollution of the air and water, while adding to the potential for global warming through the greenhouse effect.
Wood is also the best insulator of all structural building materials, with millions of tiny air cells trapped within its cellular structure providing a barrier against heat and cold. An inch of wood is 15 times as efficient an insulator as concrete, 400 times as efficient as steel, and 1,770 times as efficient as aluminum. So, homes and other buildings built with wood require far less energy to heat and cool, thus conserving fossil fuels and coal.
Another benefit of using wood is that it is reusable, recyclable, and biodegradable. Inorganic materials not only require excessive energy to produce, but also to recycle or dispose of them when their use has been terminated.
Okay, but aren’t we running out of trees by harvesting so many of them for the needs of a swelling population? No, not at all. Each American does use the equivalent of a 100-foot, 18-inch diameter tree every year for wood and paper products. But 4.2 million trees are planted every day, which results in 5.8 trees a year for every American.
More wood is grown each year in the U.S. than is harvested or lost to disease, insects, and fire. Growth exceeds harvest by 28%. It’s no surprise, then, that the nation has more trees today than it had 75 years ago, or that about a third of the entire United States – 747 million acres – is covered with trees. Or even the fact that this amount of forestland is two-thirds of what existed in pre-Columbian America some 500 years ago.
A major reason that trees are so plentiful in America is because people plant and grow them for use as wood products. These trees also provide important environmental benefits, ranging from windbreaks, shade, and soil stabilization to pure aesthetics, wildlife habitat, plus improved air and water quality.
Forests are oxygen factories and greenhouse exchangers. Growing just one pound of wood in a vigorous younger forest removes 1.47 pounds of carbon dioxide from the atmosphere and replaces it with 1.07 pounds of life-sustaining oxygen. Carbon dioxide accounts for about half of the world’s greenhouse gases, which trap solar rays. An old forest reverses the process, removing oxygen and emitting carbon dioxide.
As long as America continues to plant and grow new trees for wood products, the environment will be the clear winner. So, in a very real sense, wood products are the most environmentally responsible building material anyone could ever use.
Southern Forest Facts
The forests of the South are often called “America’s Woodbasket.” Here are just a few of the many reasons why:
- 214 million acres or 40% of the United States’ forestland is in the South.
- The South grows 22% of the nation’s softwood timber and 43% of the hardwood timber.
- By volume, the four most abundant Southern softwood species are the Southern Yellow Pines (loblolly, slash, longleaf, and short leaf), making up one-third of the total inventory.
- Annually, 10 billion board feet of wood is harvested in the South (1996).
- Each year, the South’s landowners (industrial and nonindustrial) plant 1.2 billion seedlings – an average of 3,288,000 trees each day. Following annual harvests, 1.6 million acres are replanted.
From the Southern Forest Products Association used with permission from Richard Wallace.
From the American Forest & Paper Association:
Wood is the building material of choice for strength, aesthetic appeal and environmental responsibility. Wood is renewable, recyclable and reusable, and stores carbon. Moreover, it is less energy- and carbon-intensive to produce than competing materials like concrete and steel.
Wood is a globally-traded commodity that supports U.S. economic growth. The U.S. is one of the world’s most diverse exporters of sustainable forest products, and in 2007 these exports reached $27.4 billion—10 percent of the industry’s sales. Wood products manufacturing employed some 460,000 people in 2008, earning an estimated $22 billion annually in the United States. With approximately 1,000 wood products manufacturing facilities, and $70 billion in product shipments, wood products manufacturing is essential to the success of many communities nationwide.