Pressure-treated wood costs roughly half as much upfront as composite decking — about $1,280–1,600 in materials for a 16 x 20 ft deck versus $2,900–3,100 for entry-level composite (2025 pricing). But add $115 per year in maintenance costs for wood over 25 years and the gap narrows significantly. If you avoid maintenance chores, composite pays for itself in avoided work within a decade.
Upfront Material Cost Comparison
Costs below are for decking boards only, not the pressure-treated framing (which is the same for both). Prices reflect 2025–2026 national averages and will vary by region and lumber market conditions.
| Material | 16 x 20 ft deck (boards only) | Approximate cost range |
|---|---|---|
| Pressure-treated pine | $1,280–1,600 | Entry-level, widely available |
| Western red cedar | ~$2,500 | Mid-range, naturally rot-resistant |
| Trex Enhance Basics (composite) | $2,900–3,100 | Entry composite |
| Premium composite (Trex Transcend, TimberTech Legacy) | $4,500–7,000+ | Top-tier composite |
| Tropical hardwood (ipe, mahogany) | $5,000–12,000+ | Premium wood, very durable |
Source: Decks.com material cost breakdown; Consumer Reports decking buying guide.
25-Year Total Cost Estimate
| Category | Pressure-treated wood | Entry composite |
|---|---|---|
| Upfront materials | $1,400 | $3,000 |
| Annual maintenance | ~$115/yr (stain, seal, occasional board replace) | ~$10/yr (cleaning) |
| 25-year maintenance total | $2,875 | $250 |
| 25-year total ownership | ~$4,275 | ~$3,250 |
The composite comes out ahead at the 25-year mark, though the result is sensitive to how diligently you maintain the wood deck and whether you hire out that work or do it yourself. If you enjoy the annual maintenance routine, wood is the better value. If you do not want to touch the deck again after it is built, composite makes economic sense.
Maintenance Requirements
Wood Decking
- Clean annually to remove mildew, stains, and organic debris
- Sand and re-stain or reseal every 2–3 years
- Replace individual boards as they crack, split, or rot
- Inspect annually for loose fasteners, lifted boards, and soft spots
- Pressure-treated pine that is not stained or sealed turns gray and rough within 2–3 years
Composite Decking
- Rinse with water and mild soap 1–2 times per year
- Use a composite-specific cleaner for stubborn stains
- No sanding, staining, or sealing required
- Inspect fasteners and substructure annually — the boards last longer than some substructure materials
Performance Differences
| Property | Wood (PT pine) | Capped composite |
|---|---|---|
| Surface temperature in sun | Moderate (insulates) | Significantly hotter |
| Wet traction | Good (rough grain) | Variable (smooth = slippery) |
| Rigidity / feel underfoot | Stiff | Some flex depending on product |
| Scratch/dent resistance | Moderate | Variable — soft composites dent |
| Color stability | Grays and weathers | Holds color for years (capped) |
| Mold/mildew | Susceptible | Resistant (capped); some uncapped are not |
| Splinters | Yes, as it ages | No |
Consumer Reports 3-year outdoor exposure testing found wood outperforms most composites in friction (wet traction) and rigidity. Some premium composite products matched wood in rigidity; uncapped composite products varied widely.
Environmental Considerations
Solid wood from certified forests (FSC-certified) has a low embodied energy and stores carbon over its life. At end of life it can be reused, composted, or burned for energy.
Composite decking has a higher embodied energy (manufacturing requires significant processing of the plastic component). At end of life, separating the wood fiber from the plastic is economically impractical — most composite decking goes to landfill.
When to Choose Each
Choose composite when:
- You want minimal maintenance for 10+ years
- You are building a primary living space where appearance matters long-term
- The deck is exposed to high humidity, ground moisture, or heavy rain
- You plan to be in the house for 15+ years to benefit from the upfront investment
Choose wood when:
- Budget is the primary driver
- You are a DIYer comfortable with periodic sanding and staining
- Matching an existing structure that is already wood
- You prefer the feel and look of natural wood
- Environmental impact of materials matters to you
Substructure Considerations
One overlooked factor: both wood and composite decking sit on a pressure-treated wood substructure (joists, beams, ledger). That substructure requires the same maintenance regardless of what you put on top.
Composite boards often last longer than the substructure beneath them. Trex, TimberTech, and Fiberon all recommend using their own hidden fastener systems — which require grooved-edge boards — along with quality joist tape to protect the top edge of each joist from moisture. Without joist tape, a composite deck can still rot at the frame even if the surface boards show no sign of damage.
If the substructure is already old when you replace wood decking with composite, budget for frame inspection and possibly partial replacement at the same time.
Fire Resistance
Composite decking is not inherently fire-resistant. Most composite products have the same or slightly better Class A ignition resistance as pressure-treated pine, but that performance depends on the specific product. Some jurisdictions in California’s fire zones require ember-resistant deck products — check with your local fire marshal or building department if your home is in a Wildland-Urban Interface (WUI) zone.
Getting Accurate Material Estimates
Board coverage varies by width. Standard composite boards are 5.5 inches actual width; some premium lines use 6-inch or 5-inch boards. A wider board needs fewer pieces per run but has fewer opportunities to correct cumulative spacing error. Narrower boards look more traditional.
For a 16 x 20 ft deck using 5.5-in. boards at 3/16-in. side gaps:
- Each board unit = 5.5 + 0.1875 = 5.6875 in.
- Boards across 16 ft (192 in.): 192 / 5.6875 = 33.75 — so 33 full boards plus one ripped board
- Boards along 20 ft: select a single-length board or plan butt joints over doubled joists
Use the deck calculator to estimate total materials for your deck dimensions. For installation specs, see deck board spacing and deck joist spacing.