ALL DECKED OUT
By Stephanie Aurora Lewis, RA, LEED
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A summertime barbecue on the backyard deck is the quintessential image of Americana. Knowing that the deck is constructed of sustainable materials may make it the quintessential image of environmental responsibility.
Decking materials are no longer confined to a variety of hardwood offerings. Sustainable composites have been introduced to the mix to widen the playing field. Composites are made of 100 percent sustainable materials, can be recycled, reduce waste thanks to outstanding longevity, and withstand severe weather conditions such as desert heat and mountain freezes. Furthermore, composites are safe because the materials do not require applications of extra chemicals such as pressure treatments, stains and waterproofing solvents. They are highly resistant to fire damage and are easy to maintain with water cleaning. The more commonly used pressure-treated (PT) wood decking materials contain chemicals harmful to human skin. It is also difficult to dispose of PT wood because of its chemical content and the greenhouse gas that the wood emits when incinerated or left to decompose.
Harvesting Recyclable Materials
The plastic and wood in composites manufactured by companies like Trex (pictured above) and Correct Building Products (at right) are made from recycled products. The wood, harvested from shipping pallets and scrap materials from hardwood flooring and cabinetry shops, is ground into sawdust and combined with recycled plastics. The plastic, polyethylene and high-density polyethylene (HDPE) are culled from recycled grocery shopping bags, post office shipping crates, yogurt cups, cottage cheese tubs, shipping shrink wrap, etc.
“Trex uses seven out of 10 grocery bags that are recycled through various in-store collection programs each year in the United States,” said Patrick Burns, Trex’s vice president of planning and development.
Amber Waves of Sustainable Fiber
Heartland BioComposites produces a composite material similar to products made by Trex and Correct Building Products (at right). However, Heartland uses wheat straw cellulose rather than wood as the natural fiber content. With a one-year harvesting cycle, wheat is a rapidly renewable resource as opposed to its wood counterpart, which has a 20 to 30 year turn-around time.
“The wheat straw cellulose is an agricultural byproduct,” said Heath Van Eaton, president, CEO and founder of Heartland BioComposites. Located in the southeastern corner of Wyoming, five miles from the Nebraska border, the Heartland BioComposites manufacturing plant is in the midst of far-stretching and plentiful wheat fields. “We work directly with farmers who keep the agricultural by-product dry and store it for our use,” Van Eaton continued.
Not Just a Token Nod to Sustainability
Many composite companies go beyond just recycling to support sustainability. They donate to the U.S. Green Building Council (USGBC) and belong to ecological organizations.
Managers at composite manufacturing facilities are also making strides to update their plants to conserve energy, recycle and manufacture their products with zero-waste. For example, Trex uses vegetable oil for the hydraulic lines to the power brakes and other moving mechanisms for its trailers. The company recycles the water used during the manufacturing process and grinds up scrap materials to reincorporate into new products.
Correct Building Products supports the Maine governor’s Carbon Challenge to reduce greenhouse gas emissions, manufacture with sustainability guidelines, and recycle building products. Because of its commitment, Correct Building Products has reduced its energy consumption by 20 percent, water usage by 30 percent, and cut down on its waste pick-up, from five runs per week to two.
Heartland BioComposites runs a zero-waste plant in which everything is recycled, including the cooling water. It reduces energy where possible and avoids toxins in the plant and administration offices.
Mix and Match Recycling
A few sustainability researchers, such as William McDonough, recommend separating synthetic and natural materials to allow for future recycling and eco-friendly decomposition. Because wood mixes with plastic to form the composite, the wood will not decompose. Yet, composite materials can be sent back through the manufacturing process multiple times and mixed into new batches of decking boards, railings, stairs, fencing, etc.
Some companies, like Correct Building Products, make it easy for their products to be recycled. “We are advocates for labeling the back of our products so they can be recycled ‘Cradle to Cradle,’” said Martin Grohman, founder and chairman of Correct Building Products. He explained that the slogan, “Cradle to Cradle,” was coined by William McDonough and is utilized by the Japanese Wood Composite Trade Association. According to McDonough’s website, the Cradle to Cradle Community focuses on optimizing “material health, recyclability/compostability, product life cycles, renewable energy use, water efficiency, water quality, and social responsibility, instead of only reducing the negative impacts of commerce ('eco-efficiency').”
In that vein, Grohman said that his company has started a jobsite recycling program to send products back to the plant for recycling (pictured below).
The Up-Cycled Product
Similar to carpet, composites are non-biodegradable but can be turned into new product after its first life. The upside is that unlike carpet, all composites are manufactured solely from recycled and rapidly renewable products.
Grohman describes composites as “up-cycled” products because they are high quality building materials “up-cycled” from waste. As a high-end building material that is also easy to use for the contractor, the most important trcait for wood/plastic or bio-composites is their use in creating an outdoor space that is sensitive to bare feet, saves waste and prevents deforestation.
References
1. Correct Deck. Correct Building Products. 07 May 2008. http://www.correctdeck.com/
2. Trex. 07 May 2008. http://www.trex.com/
3. Heartland BioComposites. 07 May 2008. http://www.heartlandbio.com/
4. Department of Environmental Protection; State of Maine. Governor’s Carbon Challenge. 08 May 208. http://www.state.me.us/dep/innovation/gcc/