The product itself may be flat, but the key shape in decking's future is a dumbbell. That's how decking experts predict the sales chart for their market will look in coming years. The bulge on one end will be taken up by low-cost wooden decking products, they say, while the bulge on the other is where you'll find much more expensive, plastics-based goods.

That evolution toward a dumbbell market is only one of several major trends that are taking place in the decking market. Among others:

• The recession-fueled resurgence in popularity for wood, which accounts for $2 billion of the $2.75 billion decking market, appears to have stopped, while demand for non-wood products has revived.
• Production of wood-plastic composites, a $650 million category today, is likely to be phased out within a few years.
• "Capped" decking–composites with an outer wrapping of PVC (polyvinyl chloride)–will grow in popularity. Decking made from 100% PVC, which now generates sales of $100 million, will combine with the capped products to gobble up the market now occupied by uncapped composites.
• Concerns over long-term looks and maintenance issues–some of them unjustified given non-wood decking's constant evolution–continue to dog non-wood products. Wood interests, newly organized, aim to exploit those fears.
• Big-box stores, which historically have played second fiddle to pro-oriented LBM dealers in sales of composite and PVC decking, are accounting for a bigger share of those segments' sales.
• A handful of composites and PVC decking manufacturers dominate the market, but they continue to see challenges from newcomers.
• Manufacturers increasingly are making their decking products as part of a suite of outdoor living materials that go beyond boards to embrace hardscapes, furniture, grills, fireplaces, and outbuildings.
• Makers and users of wood treatments see potential in several new technologies, such as heat-treated and acetylated wood, though most are unlikely to take hold in 2011.

It all adds up to confusing times ahead. "This year, you're going to see a big move in the industry," Kevin Brennan, TimberTech's senior vice president for sales and marketing, told participants at Principia Partners' wood-plastic composites conference last fall. "But we're not sure where the market is going to go."

Shifting Sales Mix Where the decking market has gone over the past few years is south. Principia's Steve Van Kouteren estimates that sales for all decking products have shrunk about 40% from their peak four or five years ago to about $2.75 billion today.

That decline is linked to the roughly 75% drop in new housing starts from the market's peak in 2006 through today, but it doesn't mean decks are any less desired by consumers. According to the National Association of Home Builders, the percentage of new homes started that include decks has wavered only slightly–between 24.5% and 27%–between 2005 and 2009.

Deck popularity varies markedly by region, however. The same NAHB report says that, depending on the census area, the percentage of new homes that come with decks ranges from 6.6% in the West South Central region (Texas, Oklahoma, Arkansas, and Louisiana) to 69% in New England. In contrast, of the nine census regions, the West South Central area ranks second-highest in percentage of homes with patios while New England ranks last.

Who sells what kind of decking also varies. It has long been gospel that stores like The Home Depot, Lowe's, and Menards account for the lion's share of pressure-treated wood sold, while pro dealers handle most of the composite and PVC decking. But Principia estimates that big boxes now account for one-third of non-wood decking sales.

And while wood accounts for two-thirds of all decking dollars, the picture is much different when one looks at the market for replacement decks, particularly in upscale areas. Christopher Grandpre, CEO of Outdoor Living Brands Inc. of Richmond, Va., which includes the 200-franchise Archadeck design-build firm, said at the Principia conference there was about a 50-50 split in the number of wood vs. synthetic products used in Archadeck-built projects in 2008. During 2009, wood's share rose to 54%, apparently because of financial worries, he said, but so far this year synthetics have recovered and now figure in 52% of the company's projects.

Until a few years ago, the non-wood side of the decking market consisted of composites, made from a mixture of plastics and finely ground wood, and all-plastic products. That changed last year with Trex Co.'s release of Transcend, a composite line in which three sides of the decking is covered with a PVC-type surface. The combination enabled Trex to sell PVC looks and durability at a lower price point than a pure PVC product.

Now others are catching up. TimberTech has introduced Earthwood Evolutions while CertainTeed is unveiling its EverNew PT decking line. Unlike Transcend, which isn't capped on the bottom, these two are fully encapsulated. That difference could be crucial, as there's a robust debate under way over whether exposing the bottom of a board hurts it.

What isn't debated is the trend toward more plastic in a deck's diet. "We see that, in a couple of years, two of every three jobs [we do] will involve some sort of low-maintenance materials," Grandpre said. Fiberon president Douglas Mancosh went so far as to say he doesn't expect any manufacturer to produce uncapped composite products two years from now.

Robert Lett agreed. "The wrapped products are what we see as the future," said Lett, vice president for sales and marketing at Wolf, a distributor.