Hardwoods 101: Finish Materials for Green Building Design
- By Eric Anderson
- April 1st, 2010
Hardwoods continue to be a popular choice among college and university design professionals for the traditional aesthetic appeal these materials offer. The natural warmth of hardwoods creates inviting spaces within classrooms, libraries, auditoriums, and other common areas. A range of rich colors and varied grain patterns make hardwoods appealing for flooring, furniture, millwork, and panels.
As interest in green building grows, hardwoods have also become desirable for their ability to contribute to sustainable design. Wood products are a natural and renewable material that can store more atmospheric carbon throughout their useful lives than is required to manufacture them.
While hardwoods provide several environmental advantages, the methods used to grow and harvest the wood ultimately determine a given product’s contribution to sustainability. Paying careful attention to wood product certifications, type of forest a product comes from, and species of wood can mean the difference between responsible and detrimental products. These are especially important points for exotic hardwoods, a class of materials for which illegal logging and deforestation has been a problem in tropical areas.
Certified Wood Products
Third-party certifications are an important way to determine whether wood products come from responsible sources. Such sources take actions to protect wildlife habitat, water quality, and sensitive ecosystems, and to ensure the rate of wood harvest does not exceed the rate of natural regeneration or growth from replanted trees.
Certified forests are managed to sustainable forestry standards developed by independent, internationally recognized programs. In addition to evaluating and monitoring forestry practices, certification programs also provide chain-of-custody standards to ensure that certification labels accurately reflect the volume of wood coming from sustainably managed forests.
Two prominent certifying parties are the Programme for the Endorsement of Forest Certification (PEFC) and the Forest Stewardship Council (FSC). Both programs operate around the world, each with regional certification standards that meet principles and guidelines for sustainable forest management. For example, the Brazilian Forest Certification Program (Cerflor) is a regional program PEFC endorses. Wood products certified by Cerflor are grown and harvested in a responsible manner specific to Brazil’s climate and ecosystem.
Intensively Managed Forests
When selecting hardwoods of any type, another important factor to consider is the rate at which the forest regenerates. This is a key factor in helping ensure an adequate supply of trees for generations to come.
There are three main types of forests: protected, multiple-use, and intensively managed (otherwise known as “plantations” or “tree farms”). Protected forests, such as those in national parks or wilderness areas, are left in their natural state to provide wilderness, diverse habitats, and protection for high conservation value forests. Multiple-use forests are harvested and either left to renew and repopulate on their own, or are replanted. They also provide other values, such as public access for many forms of recreation. Plantations are intensively and sustainably managed to maximize annual wood yield, while protecting important forest values such as water quality and biodiversity.
The primary advantage of plantations is that they can produce more volume of lumber per acre annually than unmanaged forests. This practice is especially beneficial when using fast-growing trees such as eucalyptus, which can be harvested in an average of sixteen years, versus 60 to 100 years for temperate hardwoods. A well-managed eucalyptus plantation can produce up to 30 times more volume of wood per acre per year than an unmanaged temperate forest. Plantations enable foresters to reduce the land footprint needed to produce wood products, allowing more land to be left in its natural state.
Another benefit of intensely managed forests is that producers manage trees for quality. This includes active pruning to support healthy growth and to reduce the number of knots. The result is stronger, straighter lumber, as well as reduced wood waste, since a greater portion of each log is suitable for use.
Alternatives to Traditional Hardwoods
Durability is another key consideration when selecting hardwoods. Colleges and universities have many diverse and high-end interior applications that are susceptible to heavy wear. These include floors subjected to repeated foot traffic, and millwork and panels frequently bumped by chairs, carts, or cleaning equipment. Hardwoods that are able to withstand high traffic can reduce the length of time between replacements, and therefore help reduce the amount of materials needed over a building’s life.
Eucalyptus, for example, is an exotic hardwood that is durable with a range of densities similar to temperate hardwoods. It compares favorably in durability to other exotic hardwoods, and has rich hues that add a contemporary or classic flourish to interior spaces.
For flooring, engineered hardwoods provide another option to consider. Manufacturers can combine exotic hardwood top layers with plywood bases for improved stability. Some products are fully certified, with both the top layer and plywood base derived from sustainably managed forests. Engineered flooring also enables manufacturers to use practically every inch of every log in the manufacturing process — either for wood products or to help fuel the mill. For healthy indoor air quality, engineered hardwoods are available with low volatile organic compound (VOC) levels.
Interest Continues to Grow
Interest in green building will likely continue to grow as colleges and universities seek to align their schools with the environmentally responsible messages they teach their students. By taking the time to identify hardwoods from certified sources, building industry professionals can play a key role in setting an example for others and work to protect the environment.
Eric Anderson is the marketing manager for Weyerhaeuser Forestlands International. Weyerhaeuser offers the Lyptus line of solid and engineered hardwood flooring, lumber, and veneer for use in a range of architectural applications. For more information, log on to www.lyptus.com or phone 800/320-9720.