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<\/figure>\n\n\n\nCutting tools:<\/strong><\/p>\n\n\n\n Use a carbide-tipped blade<\/strong> on every cut. Standard wood blades chip the cap layer on capped composite boards. This is the trade-standard choice \u2014 it’s not optional on a quality install.<\/p>\n\n\n\n Layout tools:<\/strong><\/p>\n\n\n\n Fastening tools:<\/strong><\/p>\n\n\n\n Materials:<\/strong><\/p>\n\n\n\n Check the spec sheet for your board profile before you order fasteners \u2014 clip dimensions vary by groove width.<\/p>\n\n\n\n No composite board performs well over a weak frame. A solid substructure is not a nice-to-have \u2014 it’s what the warranty depends on.<\/p>\n\n\n\n Building new:<\/strong> Use pressure-treated lumber rated for ground contact at posts and footings. In freeze-thaw climates, footings must go below the frost line, or posts will heave over winter. Attach the ledger board to the house per IRC Section R507<\/strong> \u2014 through-bolts, not nails, with proper flashing and a moisture barrier behind it. Use joist hangers at every connection.<\/p>\n\n\n\n Reusing an existing frame:<\/strong> Inspect every member for rot. Press a screwdriver into any soft spot \u2014 if it sinks, that joist comes out. Check that the frame is level across all members, and verify joist spacing meets the composite spec. One bad joist causes a board to flex, creak, or crack. Find it before the boards go down.<\/p>\n\n\n\n Composite boards don’t hide or fix frame problems. They just make them harder to spot later.<\/p>\n\n\n\n Joist spacing is the most common frame mistake on composite installs. The spec is tighter than standard wood framing \u2014 and it matters more than most contractors expect.<\/p>\n\n\n\n For straight-run installs<\/strong>, space joists 12″\u201316″ on center (300\u2013400 mm). For diagonal patterns<\/strong>, drop to 12″ on center (300 mm). Diagonal boards span a longer distance corner-to-corner across each joist, so the frame needs to be tighter.<\/p>\n\n\n\n LastElegance boards are rated for 12″\u201314″ on center<\/strong> (300\u2013350 mm). Always confirm with your product’s installation guide \u2014 board thickness affects the span rating. Thinner profiles need tighter spacing.<\/p>\n\n\n\n IRC R507.6 covers deck framing connections. Follow it.<\/p>\n\n\n\n Composite boards don’t rot. But the lumber frame below them can \u2014 and that’s a structural risk worth taking seriously.<\/p>\n\n\n\n Keep at least 12″\u201318″ of clearance between the bottom of the frame and grade. This lets air move and moisture drain away from the frame. Without it, the substructure sits in a humid zone and wears faster.<\/p>\n\n\n\n Local building codes may require more than 12″. Check before you pour footings.<\/p>\n\n\n\n Five minutes of layout planning here prevents a half-day of wasted cuts later.<\/p>\n\n\n\n Snap a chalk line<\/strong> parallel to the house to set your starting reference line. Then decide on your layout direction:<\/p>\n\n\n\n Board count calculation:<\/strong> Measure total square footage. Divide by your board’s coverage width. Add 10% for cuts and waste \u2014 more if you’re going diagonal. On a 300 sq ft deck with 5.5″ (140 mm) boards, you need about 73 board lengths before waste. Add 8\u201310 more for the 10% waste factor.<\/p>\n\n\n\n Before you lay the first board, check where the last one will land. If the final board is less than 2″ wide after a rip cut, shift your starting line now. A narrow strip at the far end is hard to fasten and looks wrong.<\/p>\n\n\n\n Most composite boards are designed for one method or the other. This isn’t a preference \u2014 it’s a spec.<\/p>\n\n\n\n Hidden fastener system:<\/strong> Clips slot into the grooved edge of the laid board and fasten to the joist. The next board’s groove slides onto the same clips. The result is consistent gapping, a clean deck surface, and no visible screw heads.<\/p>\n\n\n\n Face screws:<\/strong> Screws go through the top of the board into the joist. Faster to install, visible when done. The right call for solid-edge profiles and budget-conscious jobs.<\/p>\n\n\n\n The key point: check your board’s groove profile before ordering fasteners.<\/strong> Get the wrong clips, and you’re making a return trip.<\/p>\n\n\n\n For coastal or high-humidity jobs, stainless steel clips only.<\/strong> Standard zinc or galvanized clips corrode in salt air and leave rust marks across the deck surface \u2014 marks that won’t clean up.<\/p>\n\n\n\n Face screws are a legitimate choice on the right board and the right job. But they need to be done correctly.<\/p>\n\n\n\n Use composite deck screws<\/strong> \u2014 not standard wood screws. The thread profile and head geometry differ. Wood screws can crack the cap layer under torque.<\/p>\n\n\n\n Pre-drill every hole.<\/strong> On capped composite boards, driving screws without pre-drilling splits the cap layer at the entry point. Cap damage voids the warranty. Set screws flush<\/strong> \u2014 not countersunk. Countersinking creates a stress point that chips out.<\/p>\n\n\n\n Two screws per board at each joist crossing. Place them 3\/4″ from the board edge.<\/p>\n\n\n\n Face screws still need proper end gaps. The screws don’t manage spacing \u2014 you do.<\/p>\n\n\n\n Here’s the full install sequence. Each step is what to do and why it matters.<\/p>\n\n\n\n Leave boards flat on-site for at least 24 hours before install. Stack them so air can move between them \u2014 not bundled face-to-face.<\/p>\n\n\n\n Composite boards expand and contract with temperature. Boards installed cold in January can buckle in July if the end gaps were too tight. This step costs no extra effort and prevents one of the most common post-install complaints.<\/p>\n\n\n\n Size your end gaps for the temperature range at your install location. A job in Minnesota in March needs more gap than one in San Diego in October. The recommended range is 5\u20138 mm (3\/16″\u20135\/16″)<\/strong> \u2014 use the larger end in cold-weather installs.<\/p>\n\n\n\n The first board sets the line for the whole deck. A small error here multiplies across every board that follows.<\/p>\n\n\n\n Snap a chalk line parallel to the house. Set the board to the line, then check the square diagonally<\/strong> \u2014 measure corner to corner in both directions. If both measurements match, you’re square. If not, adjust before you fasten anything.<\/p>\n\n\n\n On hidden clip installs, the house-side edge of the first board gets face-screwed into the rim joist or ledger. The field side gets its first set of clips.<\/p>\n\n\n\n Pro tip: always check the square before driving a single fastener. Misalignment at the start compounds by the time you reach the far end.<\/p>\n\n\n\n The slot stainless steel clips into the grooved edge of the laid board. Fasten each clip to the joist \u2014 one clip per joist crossing.<\/strong> Slide the next board’s groove onto the clips and press into place.<\/p>\n\n\n\n Repeat across the deck. Every 4\u20136 boards, check alignment with a tape measure. Small drift adds up fast and becomes visible before you’re halfway across.<\/p>\n\n\n\n When boards need to be spliced mid-run, stagger the joints.<\/strong> Never end two adjacent boards on the same joist.<\/p>\n\n\n\n The last board almost never fills the remaining gap exactly. Plan for a rip cut.<\/p>\n\n\n\n Measure the gap. Subtract the required expansion gap. Rip the board to width with a miter saw or circular saw \u2014 carbide blade, cut from the face side down.<\/strong> Composite can chip on the underside if cut from below. Score the cut line with a utility knife first \u2014 this reduces cap layer chipping on thin profiles.<\/p>\n\n\n\n The outer edge of the last board gets face screws<\/strong> \u2014 clips can’t engage on the far side. Allow 1″\u20131.5″ (25\u201338 mm)<\/strong> of overhang past the rim joist on the outer edge.<\/p>\n\n\n\n Fascia covers the frame and board ends along the outer perimeter. It’s what most people see from the yard.<\/p>\n\n\n\n Cut the fascia to length with a miter saw. Miter outside corners at 45\u00b0. Face-screw into the rim joist. Match the fascia color to your deck surface \u2014 LastElegance fascia boards are available in every decking profile color.<\/p>\n\n\n\n Leave expansion gaps at fascia board joints \u2014 same spec as the deck surface (5\u20138 mm). If the deck includes stairs, apply fascia and stair treads in the matching color for a clean, finished look.<\/p>\n\n\n\n Railings go in after the deck boards are down. There are two mounting methods.<\/p>\n\n\n\n In-frame (embedded):<\/strong> Posts set through the deck frame into footings below. Stronger and preferred on elevated decks. This needs to be planned before the frame is built.<\/p>\n\n\n\n Surface-mount:<\/strong> Post bases bolt to the top of the deck frame. Faster and more common on retrofits. Requires correct torque specs and the right base plate for the deck height.<\/p>\n\n\n\n Per IRC Section R312<\/strong>, railings are required when a deck is 30″ or more above grade. Minimum railing height is 36″<\/strong> for residential and 42″<\/strong> for commercial or decks above 30″ in public settings. On decks over 5 ft above grade, get the post anchor spec engineered for the load.<\/p>\n\n\n\n These six mistakes account for most composite deck callbacks. Everything is avoidable.<\/p>\n\n\n\n No special steps are needed immediately after installation. Let the deck sit for 24\u201348 hours before heavy foot traffic, and rinse off any sawdust or debris left from cutting. After that, occasional cleaning with soap and water is all that most composite decks need to stay in good shape.<\/p>\n\n<\/div>\n<\/li>\n Yes \u2014 if the frame is sound. Check the existing substructure for rot, verify joist spacing meets the composite spec, and confirm the frame is level across all members. If it passes inspection, you can install it directly over it without rebuilding the frame.<\/p>\n\n<\/div>\n<\/li>\n A two-person professional crew using hidden clips can typically lay 150\u2013200 sq ft per hour on a straight-run deck. A 300 sq ft deck surface takes roughly half a day to a full day, not counting framework or finishing. Diagonal layouts and picture-frame borders add time.<\/p>\n\n<\/div>\n<\/li>\n Composite can go in year-round, but temperatures between 50\u00b0F and 85\u00b0F make the job easier and reduce acclimation variables. In cold weather, boards are near their minimum contracted state \u2014 leave slightly larger end gaps for summer expansion. In hot weather, the opposite applies.<\/p>\n\n<\/div>\n<\/li>\n Hidden stainless steel clips are the best choice for grooved-profile boards \u2014 they create consistent spacing and leave a clean surface with no visible screw heads. For solid-edge boards or face-screw installs, use composite deck screws, pre-drill every hole, and set screws flush.<\/p>\n\n<\/div>\n<\/li>\n<\/ul>\n<\/div>\n\n\n\n
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Start With a Solid Deck Frame<\/h2>\n\n\n\n
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<\/figure>\n\n\n\nJoist Spacing for Composite Decking<\/h3>\n\n\n\n
Install Pattern<\/th> Recommended Joist Spacing<\/th><\/tr> Straight run<\/td> 12″\u201316″ on center<\/td><\/tr> Diagonal (45\u00b0)<\/td> 12″ on center<\/td><\/tr> Picture-frame border<\/td> 12″ on center at border joists<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n Drainage and Ventilation Under the Frame<\/h3>\n\n\n\n
Plan Your Board Layout First<\/h2>\n\n\n\n
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Hidden Fasteners or Face Screws?<\/h2>\n\n\n\n
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<\/figure>\n\n\n\nInstalling Without Hidden Fasteners<\/h3>\n\n\n\n
Step-by-Step: Installing the Deck Boards<\/h2>\n\n\n\n
Step 1 \u2014 Let the Boards Acclimate<\/h3>\n\n\n\n
Step 2 \u2014 Set the First Board<\/h3>\n\n\n\n
Step 3 \u2014 Clip and Lay Each Board<\/h3>\n\n\n\n
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<\/figure>\n\n\n\nStep 4 \u2014 Cut and Fit the Last Board<\/h3>\n\n\n\n
Step 5 \u2014 Finish with Fascia Boards<\/h3>\n\n\n\n
How to Install Composite Deck Railings<\/h2>\n\n\n\n
Mistakes That Slow Down the Job<\/h2>\n\n\n\n
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Frequently Asked Questions<\/h2>\n\n\n
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Is there any special maintenance required right after installing composite decking?<\/h3>\n
Can I install composite decking over an existing wood deck frame?<\/h3>\n
How long does composite deck installation take?<\/h3>\n
What is the best time of year to install composite decking?<\/h3>\n
What are the recommended fasteners for composite decking?<\/h3>\n