Installation system opens market for elevated stone decks, patios, stairs

For years, decks, elevated patios and balconies have been popular choices for homeowners when designing or remodeling their outside living spaces. Until recently, options have been limited primarily to wood or composite materials since natural stone, pavers and tile—while aesthetically pleasing—were too heavy and difficult to install on traditional wood joist framing.

Silca Systems provides a durable structural surface for natural stone and manufactured pavers.

A new durable, plastic polymer grid system is facilitating the installation of stone up to 3-in. thick for elevated surfaces. Designed to support the structural load across a 16 inch on center span, the system effectively opens up the entire range of stone options for elevated surfaces to include the use of natural stone pavers, travertine, pavers, slate, marble, and tile.

“With traditional deck materials, it was nearly impossible to use stone on any elevated surface,” explains general contractor Jim Richardson of Richardson Brothers Construction & Demolition, Kendall, N.Y. “I wanted to offer stone decks to my customers, but any underlayment would have trapped moisture. Plus, the joist system would have to be significantly reinforced to support the weight.”

According to Richardson, whose company builds and remodels high-end, custom homes, many customers are naturally attracted to stone because it adds substantial value to and increases the aesthetic appeal of their homes while requiring little maintenance. “In my opinion, no composite deck can compare to the beauty of a stone deck,” he adds. “There’s something about the stone that adds style and class and just feels solid.”

Upstate New York weather can dictate the use of elevated surfaces for non-deck areas. Due to the region’s freeze/thaw cycles, installing stone directly on the ground can have unexpected consequences. “Even with thorough base preparation, the freezing ground, frequent thaws and ground settling make it very difficult to install stone on the ground,” Richardson explains. “As the years pass, pavers tend to heave up and down, requiring further upkeep and maintenance.” By elevating the stone, he notes, “there is no more heaving, and the grass doesn’t grow between the pavers.”


The installation of a stone deck with Silca Grates is comparable in cost to traditional wood or composite decks, depending on the type of stone used. “When you compare by square footage, labor and material for installation, the costs for stone decks are very similar to wood or composite decks,” Richardson affirms.

Designed and manufactured by Sare Plastics, a custom injection molding operation, the Silca System is a deck inlay subflooring grid that can be used on new decks or retrofit applications, and is certified to meet International Code Council standards. Silca Grates are based on the hexagonal structure of beehives, manufactured from engineered polymers into 1.5-in.-thick grids, and ensure a structural surface for natural stone and manufactured pavers.

Silca Grates are fastened to deck joists 16 inches on center using four 3-in. deck screws coated for pressure treated lumber. The grates can easily be cut to any length or contour using a circular, table or reciprocating saw. “I had never seen anything like it before, but was amazed at how easy it was to cut and install to match the shape of any elevated structure,” says Richardson. “I can use it to build anything my customers desire using stone, slate, or bricks—including two-story decks, two- or three-tier decks, and stairs.”

Richardson adds that the system can even accommodate the use of sand, whether as foundation to even out irregular stone or polymeric grades between pavers, by first installing several layers of non-woven textile on the fastened Silca Grates.

The system also suits the do-it-yourself market. Sherwood, Ore., homeowner Mark Batz was looking to replace a well-worn 25-year-old cedar deck. Recurring pressure washing and mandatory sealer treatments every few years were taking their toll on Batz, who was looking forward to relaxing on his deck rather than maintaining it.

Wood decks can warp, crack, distort, split, fade, and promote mold and mildew; to maintain them, homeowners must seal the wood on an annual or semi-annual basis, along with replacing broken screws and individual boards. When Batz came across a local contractor looking to discard several truckloads of used pavers and sand from a recent municipal project, he decided to use the material to install two ground level patios in his backyard. His next idea was to remodel his elevated wood deck as well. After conducting some research on “elevated stone or paver decks,” he discovered the Silca System.

Batz purchased the product and then installed the pavers on the grates with the help of a contractor friend who also assisted in obtaining the required permits for the project. He then utilized the remaining pavers and Silca Grates on some stairs and even created a hardscape pathway to match the deck.

Batz says the grates were easy to work with despite some intricate deck features. “I had to create very specific shapes to fit several octagonal breakfast nooks,” he explains. “We used a circular saw with a blade for plastic and the grates cut like butter. They were so easy to install … I recommend [the Silca System] for anyone that is trying to build an outdoor surface elevated above ground. Even the inspector said he had never seen an elevated stone deck before, and was impressed.” — Silica Systems, Alliance, Ohio, 330/821-1585;