outdoor flooring–underlayment system questions and answers for better outdoor living

This is a structral underlayment system used for outdoor floors. It can be placed over wood or metal joist framing or on a pedestal system. It is designed to support natural gauged stone or tile, brick, concrete or stone pavers. Use system in place of other materials used for elevated decks or roof top terraces. It is suitable for any outdoor flooring for all types of outdoor living spaces either residential or commercial. There are no height restrictions.

No. The Outdoor Floor System™ weighs only 8–10 lbs. per square foot. This is the combined weight of the Outdoor Floor System™ underlayment and an average weight of a 1/4"–1/2" gauged stone or tile. This falls within the "10-15 lbs./sq' of dead load" calculations for residential deck construction. Under these conditions the Outdoor Floor System™ can be placed over conventionally framed deck structures with joist spacing 16"–24" O.C. A roof top terrace will also only need to be designed for standard load conditions.

NOTE: PAVER DECK applications will be 10–20 lbs./sq' dead load and will require additional structural reinforcement. Consult a licensed Structural Engineer.

No. The Outdoor Floor System™ is not a coating or membrane. It is a structural underlayment designed to support solid surfaces. The open structure of the outdoor floor underlayment and the open installation of finished srufaces allows water to pass through to the ground below. The stones are placed with an average 1/8" open grout line—no grout is used. The open joints allow free drainage and room for expansion. This drainage method also means that the deck can be constructed as level outdoor floor. A Paver Deck is dry laid edge to edge. Water drains between the pavers as it does in a traditional paver patio. For a dry space below use an under deck drain system (see next question) or traditional waterproofed sub-deck.

Yes. Any of the under deck drain products that catch and redirect water that flows through the deck may be used with the Outdoor Floor System™. See AFFILIATE products.

Yes. The Outdoor Floor System™ can be used with any exterior waterproof membrane. It has no direct impact on the material selection. There are four big advantages to the Outdoor Floor System™ system in this application. (1) Cost Savings: The lightweight nature of the Outdoor Floor System™ means standard framing to support the load instead of reinforced framing for traditional heavy concrete or mudset methods. (2) Flat Terrace: Since water drains through the Outdoor Floor System™, the finished terrace can be installed as a level outdoor flooring surface. This means no unsightly scores or slopes to direct water to drain points. (3)Installation Flexibility: The Outdoor Floor System™ can be placed over the waterproofing in a variety of ways depending on the design considerations; on sleepers, on pedestals or on interlocking pads. In all methods, the Outdoor Floor System™ structural underlayment never comes in contact with the waterproofing. (4) Removability: The PierdeX® underlayment panels are 32 x 32 and can be removed at anytime to access the waterproofing surface without damaging the finished surface. The GratedeX® Floating floor installation can also be installed with removable panels. See INSTALL sequence.

No. Although the GratedeX® Outdoor Floor System™ is sufficiently strong to be placed over an existing wood or composite decking surface, t's just not recommended. (1)This would be redundant since the GratedeX® underlayment is strong enough without the decking boards. (2)The decking boards will degrade and fail before the GratedeX® system shows signs of aging. When the deck boards fail the entire structure becomes compromised because the underlayment was not fastened to the framing.

Yes. The GratedeX® system can cover an existing cracked patio if the subgrade is stable. The finished patio can be installed as a level surface with positive drainage. And with the GratedeX® underlayment, no cracks will migrate through the new finished stone surface. It can also be placed over any solid bearing surface. Each GratedeX® panel is supported by the Ped-Tite® interlocking pads. See INSTALL sequence.

The GratedeX® underlayment panel is 1" thick. The PierdeX® underlayment panel is 1-1/4" thick. The stone surface is 3/8"–1/2" thick. The combined thickness of the GratedeX® decking surface is the same as standard lumber: between 1-3/8"–1-1/2". The combined thickness of the PierdeX® terrace surface is 1-5/8"–1-3/4".

NOTE: The thickness of PAVER DECK applications will vary based on the paver thickness (between 1"–2"). Consult a licensed Structural Engineer.

To dress the factory edge of the GratedeX® underlayment panel, cover with a "Z" metal flashing material. This material measures 1"x 1-1/2". It's available at most building centers in a prefinished brown or gray. For a stainless or copper finish, contact a local custom gutter manufacturer or contractor. Wood can also be used to trim the face either flush top or with the stone overhanging the top of the wood trim. If panels are cut leaving cut ends or edges, these should either be placed to the outside edge and trimed with the "Z" metal flashing or finished with a sealer. In addition to covering the outside edges of the GratedeX® with metal trim, it can also be finished with matching stone or tile.

NOTE: PierDex™ Outdoor Floor System™ panels should not require edge treatment since most installation designs require parapet walls to retain the outside edges of the finished terrace surface.

The key to its strength and stability is the Outdoor Floor System™ underlayment. This high strength, FRP panel has dimensional stability and minimal deflection under load conditions. It requires no additional surfacing material to achieve its strength. This solid underlayment adds reinforcing strength to a stone/tile surface and bearing strength to a dry-laid paver surface. See PRODUCT SPECS at the top of the page.

Yes. Under an ASTM #E72-98 test, the system withstood 6282 lbs. of force with no failure, a maximum 1.47" deflection and a maximum .35" set deflection.

NOTE: This degree of lateral strength is achieved by using the Weld-Tite® adhesive to bond GratedeX® panels edges edge-to-edge. See PRODUCT SPECS at the top of the page.

The Outdoor Floor System™ can be covered with any gauged natural stone, manufactured tile or brick or concrete pavers. See your local dealer/supplier for best selections for your area. Certain material conditions do apply. See PRODUCT SPECS at the top of the page.

Any gauged natural stone or manufactured tile should be suitable for exterior applications. The attachment method using the flexible Hold-Tite® adhesive ensures a permanent bond even in extreme conditions. All paver products are suitable for these conditions.

If a stone or tile cracks it may not have to be removed. The flexible nature of the Hold-Tite® adhesive maintains a permanent and flexible bond even in these conditions. If the stone or tile or breaks it can be removed and replaced. To do so, break the stone into pieces, pry them from the Outdoor Floor System™ underlayment being careful not to chip adjacent stones, scrape the remaining adhesive from the underlayment and place the new stone with fresh adhesive.

Yes and No. The Outdoor Floor System™ is sold as a system with the component parts included in the system package necessary for installation. Additional individual component parts can be purchased at the time an order is placed and for a period of 30-45 days following delivery of an order.

The installation process is simple and intuitive. Others have successfully installed the product using a few simple tools; a power saw with a segmented diamond blade to cut the GratedeX® panels if necessary along with appropriate safety glasses and resperator, a hammer to set the Bite-Tite® fasteners and a cordless drill to set the fastener screw. That's it. You will find this to be a simple process to create a durable and beautiful stone or tile outdoor floor.

No. These services are best provided by a Landscape Architect, a Designer, Engineer or contractor in your area. We are happy to answer any questions to help you and your design professional incorporate the Outdoor Floor System™ into your project. We are always available to answer questions from your local consultants.

Multiply the length x width of the area to determine the total square feet. Divide this number by 16 sq' for the number of GratedeX® underlayment panels and by 7 sq' for the number of PierdeX® panels. Calculate the number of stones to cover this area + waste (1-3% or more). You can also use the online ESTIMATE-ORDER link found at the top of the page to calcualate real-time cost for the Outdoor Floor System™. You will have to contact your local dealer for stone/tile cost.

The product is sold per square foot in 16 sq' increments or 48"x48" for the GratedeX® underlayment panels and in 7 sq' increments or 32"x32" for the PierdeX® underlayment panels. The price includes all fasteners and adhesives required for the selected application method. Minimum panel quantities do apply. Stone/tile/pavers or other finished surfaces NIC.

Yes. There are discounts offered in all customer categories. To access price discounts, register a NEW ACCOUNT and submit an RFQ. Your pricing will be based on your customer type classification and the volume of your order.

The prices for both material and installation cost will vary depnding on the application and the Outdoor Floor System™ component mix. In general, this is less expensive than traditional mud set stone decks but more expensive then composite decking. In value and beauty it's unmatched. In installation, it's simple creative beauty.

Most codes call for a minimum drainage grade of 1/4" slope/ft or 1/4:12. This would be a 1.125 degree slope. A 1" slope/ft or 1:12, 4.5 degrees could safely support a Ped-Tite® pedestal to level. A steeper slope than this could be a problem. To create the level pedestal, cut the bottom of the 4" ABS pipe to match the slope, 1.125 degrees, and cut the top square to the face. When the Ped-Tite® connectors are glued to the bottom and top of the precut ABS pipe and placed in position, the pipe should sit vertical and level.

Yes and No. The bottom of the Ped-Tite® pad has a smooth bottom that will not cut the waterproofing. Adding an extra layer of material under each pad may be helpful in the long-term an is a low cost benefit. In many cases, scrap material from the waterproofing can be used for this application. Cut material into 8"x8" squares.

Yes and No. The Ped-Tite® pedestal connector pad can be glued to the waterproofing with the Hold-Tite® TA adhesive. Be sure to check with the waterproofing manufacturer for material compatibility. This is not necessary although in most cases since the weight of the underlayment floor system holds the Ped-Tite® pedestal connector pad in position.

There is a temperature limit. The material should not be used below 32° F. Optimum temperature is 55°– 80° F for best workability and achieving a 24 hour set and 7 day full cure. Colder temps thickens product making dispensing difficult and slows curing. Warmer temps thins product making it more fluid and speeds curing.

Yes. Pool side is not a problem. The underlayment is virtually inert to moisture absorption. And It can tolerate low salt and chemical conditions such as pool side and sea water. The other components as well, such as the adhesive and SS fasteners, are suitable for these conditions. In addition, these qualities also have the added benefit near zero support for bacteria and mold growth.

No, Maybe. If you select a manufactured porcelain tile, there are some manufactures who make tile specifically with a more textured surface for better traction in outdoor applications. Some natural gauged stonemay also have a more textured surface but these also tend to be less uniformly gauged. In most geographies this is not an issue. Each case should be evaluated individually. Your local stone/tile supplier should be able to give you specific guidance on this question.

Yes, That's one of the great things about the Outdoor Floor System™; it's non-combustible. Our outdoor floor underlayment has a Class 1 fire rating, and the finished stone or tile surface is not combustible. And the feet of a chiminea or other patio furniture will not be a problem either as long as the point of contact has a flat spot and not a pointed tip.