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*Composite Decking*

Composite Decking is the way of the future for decking surfaces. Maintenance is minimal, Boards don't rot or warp, most colors are warranted for 15 years or more. Manufacturers have come out with matching railing systems that greatly enhance your deck. You can even mix colors and textures from different manufacturers to create custom looks!

Here is a guideline for working with composite decking. Most brands are installed in a similar fashion, but it is always a good idea to read their instructions also.

Cutting and Drilling

When working with composite decking, saw blades and router bits with carbide tips are recommended. For best results, use blades with two teeth per inch. To avoid clogging when drilling holes, frequently remove shavings by raising the drill bit out of the hole.

Spacing

Composite decking and skirting will expand and contract with changes in temperature. The amount of expansion and contraction will vary depending upon board size and temperature. Smaller boards will expand less and larger board sizes will expand more. When installing decking, side-to-side spacing must be a minimum of 1/8" between adjacent boards.

End-to-end spacing between boards must be approximately 1/16" for every 20-degree increment of temperature difference between the temperature during installation and the maximum expected summertime temperature in your area. Butt joints of boards must be staggered. A sister joist may be utilized at the butt joint to provide a greater fastening area. Example: 80 degrees F at time of installation and a maximum expected summertime temperature of 100 degrees F equals an end-to-end spacing of 1/16".

Fastening

Screws, nails, pneumatic fasteners or one of many hidden fastening systems available can fasten composite decking. Consult your building professional to ensure selection of fasteners is compatible with your joist and substructure material. The fastening decision is solely the responsibility of the contractor, installer or homeowner. Whatever fastener you choose to use, a stainless steel version of it will give you the best performance.

Like wood, pre-drilling the end/edges of the boards is required to avoid splitting or cracking. Pre-drilling is also required in cold weather. When pre-drilling, we recommend that the drill bit diameter be the same diameter as the fastener shank. Fasteners must be spaced at a minimum of ¾" from the end of the board and 1" from the edge of the board. Skirting must be fastened with 3 fasteners every 8" on a solid surface.

Decking must be fastened at every joist. Two fasteners are required at the end of the board. Make sure joists are level.

A greater force is required to drive fasteners into decking especially when installing in cold temperatures.

Wood/Composite Screws-- Nominal 1" thick boards require a #8-2 ½" or longer screw for fastening. Nominal 2" thick boards require a #8-3" or longer screw for fastening.

Nails-- Hold nails by hand until they are driven ½ the length of the fastener into the decking.

Pneumatic Nailer-- Constant air pressure must be used to drive the nail head flush with the top of the deck board. When using pneumatic nail guns follow the nail gun manufacturer's installation and safety instructions.

String Line--The use of a string line to align fasteners/boards is recommended to enhance the appearance of your finished deck. (Do not use a chalk line)

Finishing Touch-Deck material will swell over fastener heads. Gently hammer the material down to cover the fastener head. To minimize this from occurring, pre-drill fastener holes.

Decking Span Chart

Maximum recommended center-to-center spans with a minimum of three joists are shown below. Composite deck boards must not be applied to a solid surface.

Center-To-Center Span

Board Size Residential Decks & Light Duty Decks, Commercial Decks, Boardwalks & Marinas, Residential Playground Equipment
1" x 4" 16" 12" 16" or less
1" x 6" 16" 12" 16" or less
2" x 4" 20" 16" 16" or less
2" x 6" 20" 16" 16" or less

Note: When diagonal (not to exceed 45") installation pattern is used; subtract 4" from the maximum span.

Composite decking has a more flexible feel than wood primarily during the heat of summer. This is a natural condition that will not affect the ability of the decking to perform as warranted. For a more rigid feel, reduce joist span spacing by 4". Decking cannot be cantilevered (overhang edge of deck) because structural support is required. Composite decking is a non-structural construction product. The decking products must not be used as a structural member; including joists, load bearing columns, stringers, or beams. For best results, add an additional joist at the butt joints to increase stiffness.

Cleaning

Semi-annual cleaning of your deck is recommended. Mild stains may be removed with commonly available deck washes containing sodium hypochlorite.

After cleaning, flush the surface of decking using a garden hose or a power washer hose with a fan-tip nozzle at a pressure not exceeding 1,000 psi to remove any excess cleaning agents.
Important Note: Sanding the surface to remove stains must not be done.

Handling

Composite decking is heavier and more flexible than traditional wood products. Use care and do not attempt to lift or carry more decking than you can safely handle at one time. Proper clothing and safety glasses must be worn at all times when working with decking.

Store material on a rigid, smooth, flat surface. The unused material should be kept covered and supported every 24". If boards become bent, most can be bent back to their original shape during application.

Building code regulations vary, and the Owner and/or Contractor must consult local building and safety codes for specific requirements prior to the application of composite decking.

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