Do You Leave Gaps Between Composite Decking?

Suppose you are planning to build a new deck or replace an old wooden deck. Then, composite decking boards are a great option that will last for decades. This low-maintenance decking material is a great alternative to wood decking. Common brands of composite decking on the market today are Trex, COOWIN, and Fiberon, whose high-quality composite decking can help you build your next big outdoor project.

In this article, we cover the basics of how to position composite decking, install fascia boards, and attach them with screws or hidden fasteners. We also cover how to align decking and joists. This guide is intended to give you a general idea of how to install composite decking boards. For a complete guide, visit the Trex, COOWIN, or Fiberon websites.

Storage of Composite Decking

The basics of building a deck out of wood or composite decking boards are the same. However, there are a few things to keep in mind when installing a composite deck.

Suppose you don’t plan to start building your deck right away. Composite decking boards should be kept flat, supported, and covered. This will prevent them from bending, buckling, or being otherwise damaged. The deck should be kept out of direct sunlight as much as possible so that the most accurate cutting and board placement can take place. This is because composite decks tend to expand with heat in warm weather.

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Orienting the Deck and Joists

Getting enough air circulation is important to keep your deck in good condition. For the area to remain dry, air must be able to move under the deck, and the extra space allows for air circulation. As a general rule, there should be at least 1.5 inches between the ground and the bottom of the joists to allow for drainage and air circulation.

Another important issue to consider when laying a deck foundation is the location of the joists. A minimum of three joists must support all composite decking boards at the time of installation. Both Trex and COOWIN specify a maximum space between the joists that can be used for different deck board orientations. For example, straight, diagonal, or picture frame decking design options.

Extra care is needed if you want the joists to carry heavy loads such as hot tubs or large plants. We recommend that you consult with a professional engineer to find out how long the span of the joists should be in order to carry a large load. If you are concerned about the appearance of the joists under the deck, painting the top of the joists black can help hide them.

Installation of Fascia Boards

Fascia is a type of non-structural siding. It is used to hide framing and make the deck look the same from all angles. Installing the fascia boards first ensures that the boards are laid with the proper overhang for a neat appearance. To allow air circulation and prevent the fascia from cracking, it needs to be installed with the same clearance and special screws.

Installation of Composite Decking Boards

Once the framing and joists are done, it’s time to start installing the composite decking. Many Trex and COOWIN composite decks have a similar appearance to the natural coloration of wood decking. For this reason, you should lay the entire deck before securing the composite deck fasteners. This will help you find areas where the color change is too close or makes the picture look odd.

To make composite decking look better, you may want to change the arrangement of the wood grain. Composite decking boards will usually have the same wood grain design. To get the look you want, try spreading out the design when installing Composite Decking.

Allow for Gaps in Composite Decking Boards

When installing a composite deck, make sure that you leave proper gaps between the boards, in the middle of the deck, and between the exterior boards and any permanent construction. These gaps are important because they allow for the drainage of water vapor from underneath the deck. In addition, it prevents the deck boards from pushing together as they expand with heat. For Trex, COOWIN, and Fiberon composite decks, the recommended gap width depends on how hot or cold it is outside at the time of installation:

When installing Trex and COOWIN composite decking, it is recommended to leave a 1/8″ to 3/16″ gap between boards and on the sides. The exact clearance depends on how hot or cold the weather is. Gaps to permanent structures can be 1/4 inch to 1/2 inch when temperatures are suitable.

For Fiberon composite decking, the gap between boards should be 1/32 inch to 1/4 inch. However, this may change depending on the temperature at the time the planks are installed. It is best to leave a 3/16-inch gap on both sides and a 1/4-inch gap between the outside planks and the fixed structure.

If your deck is made of metal joists and framing, they will expand differently than wood. As a result, the minimum clearance for deck boards will be different. For specific details, check the installation manual that came with your product.

Once you are happy with the look of the composite decking and have laid out the entire deck. Then you can start fixing the composite decking.

Securing Composite Decking Boards

One of the great things about composite decking is that it looks neat when installed. There are two different ways that Trex and COOWIN can do this. So make sure you read the instructions carefully and have the correct fixings ready before you start. Installing composite decking is easy if you know what to do from the start.

For all composite decking boards, the best fasteners are the matching hidden fasteners. There are also many screws on the market that are made specifically for composite decking. These screws will not crack or break composite decking boards when installed. On the sides of these composite decking boards, there are grooves to hide the fasteners.

It is a good idea to use matching clips and fasteners, and hidden fasteners when using COOWIN trim boards. In order for these composite deck special screws to work, they need to be placed in the holes that have been punched. Then cover these holes with plugs. These screws can be color matched to most of COOWIN’s composite decking boards, so the whole deck looks very neat.

For extra security, each end of each board of a composite decking board should be screwed twice to the joists, and the end-to-end joints should be attached to both joists. Trex, COOWIN, and Fiberon boards are available in the necessary lengths to be screwed to the ends of the boards. This will prevent the deck from breaking during installation and during future expansion and contraction.

Summarizing

It is important to leave proper gaps between the composite decking boards. This ensures that the deck will allow for proper drainage and air circulation. In addition, these gaps accommodate natural fluctuations in temperature, humidity, and composite expansion and contraction, reducing the risk of warping, buckling, or cracking over time.

Homeowners simply follow the manufacturer’s guidelines and leave the recommended spacing between boards. That’s all it takes to ensure the longevity and structural integrity of a composite deck, allowing them to enjoy their outdoor space for years to come.