The Low-Down on Sustainable Decking Materials

Seven years ago I began building my dream house, intent on making it both low-maintenance and energy-efficient. I loved the idea of a large deck facing my expansive westward mountain views. However, having had wood decks on a previous house, I knew I didn’t want to spend half my summer weekends staining and waterproofing. I settled on composite decking made of recycled wood fiber and plastic, which I believed would cut down on maintenance and reduce my home’s impact on Mother Nature, as composite materials are said to last 20 years or more.

Little more than five years later, however, I found my composite deck disintegrating where it was exposed to sun and rain. I felt like I had been taken for a ride. My experience isn’t unique, unfortunately. Selecting sustainable decking materials that are durable and reliable can be difficult. “‘Green’ has such a large definition,” says Rick Goldstein, co-owner of MOSAIC Group Architects and Remodelers in Atlanta. “There are no perfect metrics. When it comes to decking, I don’t know of any products that are truly green–they just have green aspects.”

So how do you know which sustainable decking materials to choose? It can be a tricky process, so doing your homework is paramount.

Wood Decking

Wood is strong, easy to work with, and can be painted or stained any color. But it can be difficult to discern which wood is sustainable. The Forest Stewardship Council (FSC) certifies lumber that was sustainably harvested, but FSC-certified wood may not be the greenest option if it’s shipped from afar. If you must choose between FSC-certified lumber from South America or Asia and non-certified local wood, choose local, Goldstein recommends. Transportation emissions are a major contributor to greenhouse gases, and if you use a local harvester, it’s easier to track where the lumber came from and how it was harvested.

While there is no centralized resource for finding locally harvested lumber, a search for lumber companies and your city name should get you started. Look for companies that directly sell the products they harvest. You can search for local retailers of FSC-certified lumber at FSC’s website. When discussing options with companies, make sure to ask about durability and weather-resistance.

Brooks Utley, design expert for the OWN network’s “Home Made Simple,” says salvaged lumber can be an excellent decking option–he made his own deck out of salvaged lumber. Salvaged wood decking makes use of a material that would otherwise go to waste. However working with salvage can present challenges. If you can’t pick pieces yourself, you may get boards that are partially rotted or discolored. And because salvaged wood isn’t likely to be uniform, installation can be more difficult. The best way to source salvaged lumber is to search online or to find local builders who are familiar with salvage. You can search for salvage yards at the Building Materials Reuse Association website. You can also order ready-to-install salvaged wood decking, but shipping the wood increases its environmental impact.

Aluminum Decking

Aluminum decks are an excellent option for durability and sustainability. Generally made with recycled content, aluminum is also fully recyclable, so any scrap from construction can be reused. Should you replace your aluminum deck one day, the deck boards, which often have the look of wood, can also be recycled instead of going to the landfill. Aluminum is likely the toughest decking product you can buy. It’s entirely water-
resistant and stays cooler than many other deck materials in summer, meaning you can comfortably walk across it barefoot. LockDry and AridDek offer aluminum decking products.

Composite Decking and PVC Decks

Composite deck boards are usually made with a combination of recycled plastic and waste wood fiber ground into sawdust. In the last couple of decades, composite decking has increased in popularity because it tends to be low-maintenance (if you purchase a reliable and proven product) and offers design flexibility. You can mix colors and create curved features easily.

However, composite decking has seen its share of troubles. “Not only do they fade, but there have been more failures with composite decks than any other type of decking material,” Goldstein says. He only uses EverGrain composite decking, which he’s had reliable success with. Utley recommends ChoiceDek or Trex, the company that pioneered synthetic alternatives to standard wood decks and whose products have been used on boardwalks in harsh, damp climates such as the Florida Everglades.

Although PVC is a petroleum byproduct, Goldstein prefers PVC decks such as those made by AZEK and Gossen for their efficient production process and durability. He points out that, although composites use recycled products such as milk jugs and wood fiber in their manufacture, finished composite products are not recyclable. “PVC is fully recyclable,” Goldstein says. “If there is waste, it can be put right back in the hopper.” Because few retailers currently stock composite decking, orders for composite materials are often sent individually, which is less efficient than large-scale shipping of PVC decking to home stores. PVC decks also tend to have the longest warranties in the business, though homeowners should be aware that PVC shrinks and swells in cold and heat. If you choose a composite or PVC deck, keep in mind that synthetic decks still require a treated lumber frame. Composite decking products buckle if not installed properly, and manufacturers don’t honor warranties if installation guidelines aren’t followed to the letter.

The sustainable decking materials you choose are largely a matter of taste, cost and your willingness to perform maintenance. The most important element of sustainability is to thoroughly research a product from its materials sourcing to its delivery and durability. Then balance the elements of sustainability with your desires.

The Cost of Decking

Raymond Desper of Valley Building Supply in Staunton, Virginia, provided price estimates for various decking materials. Prices vary by region (prices don’t include fasteners).

Wood: $1 to $2 a square foot for treated lumber; $12 a square foot for ipe (a high-end wood product)

Salvaged Wood: Prices vary widely; check local building codes to ensure salvaged wood decks are allowed in your area

Aluminum: $7 to $9 a square foot

Composites: $4 to $8 a square foot depending on brand

PVC: $8 a square foot

Treat Your Deck Right

While deck installation is a job for a professional (unless you have substantial building experience), you can save on labor by doing your own staining and preservative treatments should you choose to install a wood deck. In the past, oil-based stains and preservatives were the only ones guaranteed to withstand the ravages of pests and weather, but a lot has changed in the last decade.

Almost all paint and stain manufacturers offer low-VOC (volatile organic compound), water-based stains and wood preservatives that are equally effective as oil-based options. While most stains and preserving treatments must be reapplied every couple of years, CedarCide is a 100 percent nontoxic sealant and preservative that lasts 20 to 30 years. It’s pricey at $50 per gallon, but over the lifetime of your deck, you’ll save a bundle.

Deborah R. Huso, a builder’s daughter who constructed her own home with sustainable features seven years ago, is a columnist for Today’s Diet & Nutrition and contributing editor with The Progressive Farmer and Blue Ridge Country.