Contractors such as Demetrius Gadson have discovered a new land of opportunity — the space beneath the untold number of decks in the U.S.

For about four years, Gadson, a principal in PGA Construction, Kennesaw, Ga., has been installing “underdeck systems” — ceiling/drainage systems designed to provide at least partially sheltered living space. These systems are generally installed beneath deck joists in new or retrofit applications, and constitute a growing market. “These systems have been around for a while, but recently they've been getting more exposure,” Gadson adds.

EMERGING MARKET “The market is just now emerging,” says Eric Smith, vice president of marketing for manufacturer Dry Under Deck, in Smyrna, Ga. “Demand is being created for this product by the end user,” — i.e., homeowners — largely thanks to growing awareness, he adds.

Indeed it is. This month one of the nation's biggest home improvement companies, U.S. Home Systems, began offering the Quality Edge underdeck system through The Home Depot outlets in Minneapolis and Atlanta. “And we have every intention of taking it to all 40 markets,” says Sean Gallagher of Pro Materials Direct (, which distributes Quality Edge.

The underdeck product's appeal to homeowners is broad and basic. “It's probably the least expensive way to get more livable space because you double the square footage of the deck,” says Keith Risser, president of Dek Drain, a manufacturer in Columbia, Md. Adds Gadson, “It boils down to price and how often the homeowner is going to use the outside area.”

Currently there are some 15 underdeck system manufacturers, contractors estimate, and products vary in design and effectiveness. Materials include aluminum and the rubber used in commercial roofing; costs range from $10 to $20 per square foot. Research vendors carefully, Gadson advises. “They may not look different, but being an installer and seeing how each system functions, there is a big difference.”

INSTALLATION IS KEY Easy installation is also a key consideration. Mike Forbes, owner of Austin Dream Decks, in Jonestown, Texas, who recently began installing the systems, says none have taken more than a day, with two people, “and that's working 10 or 12 feet in the air.”

Underdeck systems can dovetail nicely with existing products to make for profitable add-on sales, contractors say. And, they report, margins can range from 20% to 40%. —Jay Holtzman is a freelance writer based in Jamestown, R.I.