Wood vs. Other Materials

Aluminum, wood, fiberglass and vinyl are all used in the construction of doors and windows, with various pros and cons. An aluminum window frame may be durable and require little maintenance, but it has a high degree of embodied energy; it is also a transmitter of heat and cold, resulting in utility costs and lower comfort levels. A vinyl frame may offer energy efficiency and weather resistance, but it will tend to fade and become brittle and is thermally unstable. Fiberglass offers good thermal stability and structural strength and a low conduction rate but is difficult to shape.

Wood has been used for thousands of years as a building material and continues to be cost-effective, aesthetically pleasing and environmentally responsible. Compared to other building materials wood has significant advantages in the following areas:

Strength, Efficiency, Flexibility. Wood has good thermal, mechanical, machining and durability properties. Its strength to weight ratio exceeds that of steel, aluminum, or fiberglass. Wood has good longitudinal flexural strength and, unlike metals where shaping can be difficult to achieve and expensive, wood can be easily and rapidly machined and glued into many forms.

Insulation.Wood contains a honeycomb of millions of tiny airspaces within the fibers, all of which create natural insulation. Wood has been shown to be 400 times more efficient than steel and 1,800 times more efficient than aluminum in window systems.

Sustainability. Trees are continually regenerated naturally and through planting, with statistics showing more forest area today than 100 years ago; forest growth in the United States exceeds harvest by over 35 percent annually. Properly cared for, wood products last for generations and wood is completely biodegradable at the end of useful life.

Life Cycle Costs.When the total life cycle of a material is considered, wood is the most environmentally friendly material. In the Athena Model, developed by the nonprofit Athena Sustainable Materials Institute, wood was found to have a lower environmental impact than steel and concrete and to have better environmental soundness as measured by energy use, production of greenhouse gases, air and water pollution, production of solid waste, and overall ecological resource use. Effectively utilizing wood stores large amounts of carbon dioxide, meaning significantly reduced global warming potential for wood products.

A Who's Who of Certifying Agencies

Certification programs in the United States and internationally have begun to promote sustainable forestry practices with the objective of assuring consumers that wood used to make a certain product - lumber included - was grown, managed and harvested using sustainable practices and meets predetermined social, economic, and environmental standards. Certification is in its early stages.

According to Portland, Oregon-based nonprofit Metafore, forest certification has been established for more than a decade and nearly 740 million acres have been credibly certified - about 7.5 percent of the world's forests.

The various certification organizations may share a common goal of achieving sustainable forestry, but they are otherwise different in approach and operation. Two organizations, the Forest Stewardship Council (FSC) and the Sustainable Forestry Initiative (SFI) are the primary drivers of certification activities in the
United States.

 

Wood Showcased in LEED® Platinum Arboretum The Visitors Center at Bernheim Arboretum and Research Forest, Kentucky's official arboretum is as green as they come. Designed by William McDonough + Partners of Charlottesville, Virginia, in a series of trellises and pergolas that bring people and nature together, the center received the U.S. Green Building Council's LEED Platinum certification, making it the first in the state and surrounding region to receive the highest award for green building practices. Nestled among evergreen and deciduous trees, the center was assembled from recycled cypress wood sourced from old H.J. Heinz pickle vats. Pine was selected to frame the windows and the full-lite, sliding stile and rail French doors, which work to create "window walls" that blur the separation between inside and outside. "We didn't want people to think they were inside a building," says Lee Rambo Bagley, AIA, of Barnette Bagley Architects of Lexington, Kentucky, the Architect of Record. The pine used in the fenestration was factory-treated with a clear water-repellent preservative that penetrates into the wood to provide effective protection from moisture, mold, decay and wood-destroying fungi. The active preservative is a combination of three fungicides which provide excellent resistance to the full range of wood-destroying fungi. "The actives are biodegradable, thus will not have cumulative harmful effects on the environment," says Bagley, noting that the finish applied to the entire building - doors and windows included - consisted of 100 percent organic flax, linseed, hemp, and soybean oils, isoaliphate and cobalt-free and lead-free driers. The trim surrounding pine-framed windows and doors came from an adjacent Jim Beam rack house that was recently dismantled. With the rack house built and the arboretum created in the 1920s, it stands to reason that the wood used in the former may have been harvested in the arboretum woods. "Using the rack house wood in the visitor center completes the circle," says Bagley. Wood is featured in the Visitors Center, which received the highest award for green building practices. Photo © 2008 Isaac W. Bernheim Foundation. All rights reserved.

 

Forest Stewardship Council

An international nonprofit, multi-stakeholder organization, the FSC was established in 1993 as the first worldwide certification system for forests and forest products. To achieve this objective, FSC developed 10 guiding principles from protection of biodiversity to respect for indigenous people's rights. The organization does not directly certify forest products itself, but accredits and oversees independent certifiers who assess forest practices of a given operation against FSC's stringent environmental and social criteria. Operations that meet those standards may identify their products as originating from a well-managed source. The certifier may also assess the "chain of custody," meaning the possession and transfer of wood and fiber from a certified forest through the different stages of production-primary manufacturer, secondary
manufacturer, wholesaler, and retailer-to the end user. Over the past 13 years, over 240 million acres globally in 70-plus countries and 80 million acres in the United States and Canada have been certified
according to FSC standards; several thousand products are produced using FSC-certified wood and carry the FSC trademark. FSC operates through its network of national initiatives in 45 countries.

Although marketed as the gold standard with the most rigorous requirements, critics feel that FSC doesn't have a corner on the forest management market and that it should not be the only certification recognized by the U.S. Green Building Council's LEED sustainable-design rating system. There is growing recognition that other certifying organizations are also credible and, in some cases, architects have shown a preference for doing their own due diligence when it comes to investigating a source's sustainability credentials. Other critics of FSC maintain that compromises have been made in the rush to certify products, particularly in tropical forests. Furthermore, traditionally, a key disadvantage of FSC has been the high cost to actually become certified. Lately, however, group certifications have helped to spread that cost among
several landowners.

Sustainable Forestry Initiative

The Sustainable Forestry Initiative (SFI) was started in 1994 by members of the American Forest and Paper Association and has since undergone a series of improvements that took it from the status of trade association to an internationally recognized independent certification program in North America with a set of measurable practices, 137 million acres enrolled with 127 million acres independent third-party certified.
In 2005, the SFI program collaborated with the premier standard setting agency American National Standards Institute to develop SFI-specific accreditation programs for auditors of forest management and chain of custody standards. In the same year, the SFI program received endorsement from the European agency known as the Program for the Endorsement of Forest Certification (PEFC) schemes, making it one of 22 PEFC-endorsed certification programs worldwide that together represent over 484 million acres of forestland. That certification expanded SFI's footprint, providing it with more opportunities to market its program and certified products outside North America.

In October 2006, SFI issued the SFI Requirements for Fiber Sourcing, Chain of Custody, and Product Labels. Today the SFI program has more than 220 program participants and chain of custody holders in the U.S. and Canada and a program with four different labels. It also allows participants to include statements regarding recovered (recycled) content. But probably the most important development came in January 2007 with the move to make SFI fully independent of the American Forest & Paper Association. Responding to continual criticism that it was too heavily influenced and controlled by industry interests, the SFI is now governed by an independent board of directors that includes nonprofit environmental groups and forest products companies in pursuit of its professed goal: ensuring sustainability of forests while giving customers and consumers a visible stamp of assurance that they are purchasing products from companies committed to sustainable forestry.

Where FSC is international in scope, SFI certifies forests in North America and has more certified forest here - 127 million acres vs. FSC's 80 million acres certified in North America.

"Both FSC and SFI are good programs and have a place," says Ben Wallace, a wood scientist with Marvin Windows and Doors. "The forest management principles are essentially the same. SFI is based on scientific forest management principles. It does a lot for the long term sustainability of the forest - from the standing tree to the finished products, and it puts more emphasis on landowner and logger education. FSC doesn't do much beyond forest management, and raises some concerns about ground log handling and road building."
"Regardless of how you feel about the individual certification programs, what's important to recognize is the huge effort the industry is making to get behind sustainable practices. It's very progressive - you don't see that with most other building materials," says Katie Fernholz, Executive Director of Dovetail Partners, Inc., a nonprofit organization that provides authoritative information about the impacts and trade-offs of environmental decisions. "Wood has very strong environmental attributes, and certification is another one to add to the list."