How to Install Composite Decking
It is very important to follow the manufacturer’s instructions when installing composite decking material. Thermal expansion is always something to be aware of when dealing with plastics. In most climates, temperatures fluctuate enough to cause an issue with how the decking is spaced from summer to winter. Composite decking tends to grow and shrink across the length of the boards as it heats and cools. Proper spacing will allow some movement without buckling.
Some composite decking materials are designed to be installed with hidden fasteners. These clip systems generally are screwed into to the deck frame across each joist and fit tightly into a cavity running down the side of the boards.
We recommend using reverse thread screws when face-screwing composite decking to eliminate mushrooming. Mushrooming occurs when a standard bugle head screw pulls some composite material above the surface during installation. The resulting raised bump isn’t very attractive. You can also use a hammer to level the surface.
Hollow decking products will leave open ends that aren’t attractive and can collect dirt, leaves, etc. Most hollow decking products sell end caps that can close the ends. Another method involves installing a racetrack or picture frame pattern perimeter to cover the open ends.
Controlling Deck Seams
It is always best to try to avoid seams on your deck surface. Butt joints tend to separate and warp as the decking material weathers. Depending on the size and shape of your deck design, this may be easy to accomplish without any effort, or you may have to make some adjustments. Applying decking diagonally can often reduce or eliminate the number of butt joists on decks that are over 20’ wide. In some cases, you may decide that it easier to use a division board to create one continuous seam across the deck surface. This technique is used to control the seam and make it appear to be a part of the design.
The field deck in this picture is 24' wide with an additional 6" picture frame border. In this case, we are staggering the butt joints every 4'. We added double 2x10 joists to support the seams. An alternative is to use a division board and create 2 decking fields.
To install composite decking with a hidden fastening system, start at the house by face-screwing the first board. Next, screw a hidden fastener clip into the groove on top of each joist. Then, slide the groove of the next board into the clips and tighten with a rubber mallet.
Decking Patterns
Installing your decking at a 45-degree angle is a popular style for decks. This can be done to reduce decking seams or just for appearance.
Installing Composite Decking
Learn about how to install composite decking. Topics include expansion and contraction issues and hidden fastener systems.
How to Build Box Steps for Your Deck
Learn how to build a set of box platforms to act as stairs for a low deck. You don't need to cut stair stringers.
Anchoring Deck Stairs
Learn how to anchor your deck stairs to a concrete landing pad or footings. Follow our step-by-step instructions with photos.
Stair Stringer Length
Learn how to measure the height of your deck and use our Decks.com Stairs Calculator to determine your stair stringer lengths.
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How to Install Composite Decking
It is very important to follow the manufacturer’s instructions when installing composite decking material. Thermal expansion is always something to be aware of when dealing with plastics. In most climates, temperatures fluctuate enough to cause an issue with how the decking is spaced from summer to winter. Composite decking tends to grow and shrink across the length of the boards as it heats and cools. Proper spacing will allow some movement without buckling.
Some composite decking materials are designed to be installed with hidden fasteners. These clip systems generally are screwed into to the deck frame across each joist and fit tightly into a cavity running down the side of the boards.
We recommend using reverse thread screws when face-screwing composite decking to eliminate mushrooming. Mushrooming occurs when a standard bugle head screw pulls some composite material above the surface during installation. The resulting raised bump isn’t very attractive. You can also use a hammer to level the surface.
Hollow decking products will leave open ends that aren’t attractive and can collect dirt, leaves, etc. Most hollow decking products sell end caps that can close the ends. Another method involves installing a racetrack or picture frame pattern perimeter to cover the open ends.
Controlling Deck Seams
It is always best to try to avoid seams on your deck surface. Butt joints tend to separate and warp as the decking material weathers. Depending on the size and shape of your deck design, this may be easy to accomplish without any effort, or you may have to make some adjustments. Applying decking diagonally can often reduce or eliminate the number of butt joists on decks that are over 20’ wide. In some cases, you may decide that it easier to use a division board to create one continuous seam across the deck surface. This technique is used to control the seam and make it appear to be a part of the design.
The field deck in this picture is 24' wide with an additional 6" picture frame border. In this case, we are staggering the butt joints every 4'. We added double 2x10 joists to support the seams. An alternative is to use a division board and create 2 decking fields.
To install composite decking with a hidden fastening system, start at the house by face-screwing the first board. Next, screw a hidden fastener clip into the groove on top of each joist. Then, slide the groove of the next board into the clips and tighten with a rubber mallet.
Decking Patterns
Installing your decking at a 45-degree angle is a popular style for decks. This can be done to reduce decking seams or just for appearance.
Best Time to Build a Deck
People often wonder when the best time to build a deck is. Learn why building a deck in winter or fall might be your best bet.
How to Demolish & Remove a Deck
At some point, it might become necessary to remove an old deck, due to age or condition. Learn more about what's involved in a deck demolition and removal project.
How to Build Box Steps for Your Deck
Learn how to build a set of box platforms to act as stairs for a low deck. You don't need to cut stair stringers.
How to Build Box Steps for Your Deck
Learn how to build a set of box platforms to act as stairs for a low deck. You don't need to cut stair stringers.
Explore Articles by Topic

Footings
Information related to installing frost footings for decks

Framing
Learn structural framing methods

Decking
Learn about wood and composite decking materials

Stairs
An in-depth look at the complex issue of how to build stairs

Railings
How to install guardrails and handrails to meet IRC code

Features
An overview on water drainage, benches, planters and lights

Design
The basics of deck design

Planning
Learn about permits and working with contractors

Porches & Patios
Build a covered deck to enjoy all seasons

Ledger
Proper attachment techniques

Care
Maintain your deck to maintain your investment

Materials
An overview on water drainage, benches, planters and lights