Choosing the right deck plank is the single biggest decision you will make when building or resurfacing a deck, because the boards dictate the look, the maintenance schedule, and roughly half the total material budget. A deck plank is simply the flat surface board you walk on, fastened across the joists, and the material you pick will determine whether you are staining every two years or hosing the surface once a season.
This guide walks through the common decking materials, standard board sizes, proper spacing, cost per square foot, and how the boards get fastened, so you can spec a deck that fits your climate, budget, and tolerance for upkeep.
Deck Plank Material Options
Decking boards fall into two broad camps: natural wood and manufactured (composite or PVC). Each has a clear personality.
Pressure-Treated Pine
The default budget choice across most of the United States. Southern yellow pine is chemically treated to resist rot and insects, costs roughly $2 to $5 per linear foot, and takes fasteners easily. The trade-off is maintenance: it needs cleaning and re-sealing every 1 to 3 years, and it tends to cup, check, and crack as it dries.
Cedar and Redwood
Naturally rot- and insect-resistant softwoods with a warm color and no chemical treatment. Cedar runs about $4 to $9 per linear foot. It looks beautiful but is soft, dents easily, and still needs periodic sealing to hold its color rather than fading to gray.
Composite (Trex, TimberTech)
A blend of wood fibers and recycled plastic with a protective cap. Composite boards from Trex or TimberTech cost roughly $4 to $13 per linear foot and need almost no maintenance beyond occasional washing. They will not rot, splinter, or need staining, though cheaper uncapped lines can fade and stain over time.
PVC and Aluminum
All-plastic PVC boards (such as TimberTech AZEK) are the lightest and most weather-proof option at around $6 to $15 per linear foot, ideal near pools and coastlines. Aluminum decking is the premium, near-indestructible tier used mostly on rooftop and fire-rated decks.
Standard Deck Plank Sizes
Decking is sold in nominal sizes that differ from the actual measured dimensions, which trips up a lot of first-time builders.
- 5/4×6: The most common wood decking board. Nominal 1-1/4 inch by 6 inch, with an actual thickness around 1 inch and an actual width of about 5-1/2 inches. Lightweight and economical.
- 2×6: A true framing-grade board, nominal 2 inch by 6 inch, actually about 1-1/2 inches by 5-1/2 inches. Stiffer and stronger, good for wide joist spacing or a more solid feel underfoot.
- 2×4: Occasionally used for a tighter board pattern, actual size roughly 1-1/2 by 3-1/2 inches.
Most composite boards mimic the 5/4×6 profile, running about 1 inch thick by 5-1/2 inches wide. Lengths are typically sold in 12, 16, and 20 foot pieces, so planning your deck dimensions around those lengths minimizes waste and cut-off scrap.
Deck Plank Spacing and Gaps
Never install decking boards tight against each other. Boards need a gap for drainage, airflow, and seasonal movement. The standard spacing is:
- 1/8 inch to 1/4 inch between boards for most materials.
- For pressure-treated lumber that is still wet from the yard, install boards nearly touching (1/16 inch), because they will shrink as they dry and the gap will open on its own.
- For dry wood or composite, use a 3/16 inch gap as a reliable middle ground. A 16d nail or a dedicated spacing tool makes a handy consistent gauge.
Joist spacing matters too. Most wood and composite decking runs on joists 16 inches on center. If you install boards at a 45-degree angle, tighten the joists to 12 inches on center to prevent bounce and sag.
Deck Plank Cost Per Square Foot
Board material drives the price, but installation labor typically doubles the number. For decking boards alone:
- Pressure-treated pine: roughly $2 to $5 per square foot.
- Cedar: roughly $4 to $8 per square foot.
- Composite: roughly $4 to $12 per square foot.
- PVC: roughly $6 to $15 per square foot.
For a 16 by 20 foot deck (320 square feet), the decking boards alone might run $700 to $1,600 in pressure-treated pine or $1,300 to $3,800 in composite, before framing, footings, railings, and fasteners. Installed, a full composite deck commonly lands between $30 and $60 per square foot all-in.
Fastening Your Deck Plank
How you attach the boards affects both appearance and longevity. There are three main methods:
- Face screwing: The traditional method. Drive two coated or stainless deck screws through the top of the board into each joist. Strong and simple, but the screw heads are visible. Use exterior-rated screws; standard interior screws will rust and stain the wood.
- Hidden fasteners: Clips that sit in a groove on the board edge and screw into the joist, leaving a clean top surface with no visible heads. Most grooved composite boards are designed for this system.
- Plugs: Face screws counterbored and covered with matching wood or composite plugs for a smooth look on solid-edge boards.
Whatever method you choose, always predrill near the ends of wood boards to prevent splitting, and keep fasteners at least 3/4 inch from board ends.
Board Profiles: Grooved vs Solid Edge
Beyond material and dimension, decking boards come in two edge profiles that determine how you fasten them.
- Grooved edge: A channel milled down both long sides accepts hidden clip fasteners. This is the standard for composite and PVC field boards and gives the cleanest finished surface with no visible screws.
- Solid (square) edge: No groove, so these boards are face-screwed or plugged. Solid boards are used at the perimeter, around stairs, and anywhere a groove would show at an exposed edge.
Many composite lines also offer a “grooved” board for the field and a matching “square” board for borders, so plan your order with both. A picture-frame border of solid boards around the perimeter hides the cut ends of the field boards and gives the deck a finished, custom look.
Estimating How Many Deck Planks You Need
To estimate board count, calculate your deck’s square footage and add 10 to 15 percent for waste, cuts, and the border. For a 5/4×6 board, each linear foot covers roughly 0.5 square feet of surface once you account for the gap between boards, so a 16-foot board covers about 8 square feet.
For that 16 by 20 foot (320 square foot) deck, you would need roughly 40 boards of 16-foot 5/4×6 material for the field, plus extra for a border and stair treads. Always order a few spares; dye lots on composite can vary between batches, and having matching stock on hand for a future repair is worth the small extra cost.
Maintenance Expectations by Material
Your long-term workload varies wildly by the plank you choose. Pressure-treated pine and cedar need washing and re-sealing or staining every 1 to 3 years to fight graying, cracking, and rot. Skipping that maintenance shortens a wood deck’s life from 20-plus years to closer to 10 or 15. Composite and PVC, by contrast, ask only for a seasonal wash with soap and water or a deck-specific cleaner. Factor that ongoing labor and material cost into your decision, because the cheaper board at purchase is often the more expensive board over a 25-year lifespan.
Final Thoughts on Choosing a Deck Plank
The best deck plank for your project balances upfront cost against long-term maintenance. Pressure-treated pine wins on price but demands ongoing sealing; composite and PVC cost more initially but essentially eliminate the annual chore of staining. Match the board size to your joist spacing, leave a consistent 1/8 to 1/4 inch gap, and use exterior-rated or hidden fasteners. Get those fundamentals right and your deck plank surface will stay flat, safe, and good-looking for decades.
