How to Install Composite Deck & Porch Railings
Composite guard railings offer a low-maintenance option for railing. Most low-maintenance decking manufacturers offer one or more railing systems to compliment their flooring products. You will have the opportunity to choose from a variety of colors, styles and options. These systems are available in kits that are relatively easy to install.
These systems use 4x4 pressure-treated wood posts covered by a sleeve and mounted to either the inside or outside of the frame. Each railing section can be easily installed between posts using brackets provided in each kit. Stair railing kits are also available for ease of installation.
SaveThis is a composite guardrail system with steel balusters. Most composite railings are sold in 6' and 8' kits. The 4x4 posts, post sleeves, post caps and post base trim are sold separately.
SaveUse a shim to adjust rail posts that are out of plumb. In this situation, we ripped a wedge off the right side of the post to use as a shim for the left side, making it plumb.
SaveFor low-voltage post lighting, pull wires through the post sleeves before securing them. Pull wires to the corner of the sleeve to prevent puncturing with rail attachment screws.
SaveCenter your top and bottom rail sections along the post sleeve. Then, attach them with the universal rail bracket. This bracket can be used for straight, angled and stair rail sections.
SaveBuild a jig using scrap material to assist in drilling the baluster connector locations. The width of this jig was cut to 1 1/4" wide to fit inside the channel in the top rail and center on the bottom rail. The manufacturer recommends 4 3/8" on center spacing for 3/4" steel balusters. If you plan on tightening your spacing of balusters, make sure you order extra balusters.
SaveSet your jig to balance the layout of your balusters along the top and bottom railing. You may choose to center a baluster or space at the center of each section of rail. The jig makes it easier to choose the most attractive layout. You don't want a baluster installed too close to the rail posts. Use your jig to pre-drill the baluster connector locations.
SaveInstall the baluster connectors to the top and bottom rails. Do not over tighten the connectors.
SaveFor 45-degree angle rails, cut a 1" section as a guide to center the railing on the post.
SaveUse a scrap piece of top cap to set up your precision cuts. This will allow you to set up your saw to the correct position before cutting each end of railing one side at a time. This method can be used for the top and bottom rails.
SaveUse a scrap piece of top cap to align the height of the stair rails with the standard guardrails. You can also use this piece to test your angled cuts.
SaveUse a scrap piece of bottom cap to test angled cuts. The bottom cap slides over the top of the bottom rail.
Interested in purchasing composite railing for your home? Check out the options on Trex.
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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