Trex Decking Cost Calculator
Estimate the cost of a Trex deck — enter your deck size, height and railing to get a low-to-high installed price and the cost per square foot. Trex composite decking typically runs $30–$60 per square foot installed.
United States — national average · 2026 prices
Material only unless stated as installed. Excludes tax, permits and local labour. Verify with local suppliers — see how we calculate.
How this calculator works
Every figure above comes from the formula below, applied to the assumptions listed. Nothing is looked up from a hidden table — you can reproduce the result by hand.
Formula
deck area = length × width
decking cost = area × material rate per sq ft × height multiplier
railing = lineal feet of open side × $25–$60 per ft
total = decking + railing, split about 45% materials / 55% labour
Assumptions & limits
- Trex is costed at $30–$60 per sq ft installed. The spread is mostly the product line: Enhance is the entry tier, Select mid, Transcend premium.
- Trex boards are wood-plastic composite with a capped shell, nominally 5.5 in wide — so board counts follow the same 5.5 in + gap coverage as wood decking.
- Trex requires 16 in on-centre joist spacing for perpendicular installs and 12 in for diagonal, which is tighter than pressure-treated wood tolerates. The framing is not included in this figure.
- Installed rates per sq ft: pressure-treated $15–$25, cedar or redwood $20–$35, composite $30–$60, PVC $35–$70, tropical hardwood $30–$60 (2026 US national ranges).
- Height multiplier is 1.0 ground level, 1.15 raised, 1.30 elevated, covering taller footings, beams, bracing and guard railing.
- Railing length is derived from the number of open sides: two sides = length + width, three = length + 2 × width, four = full perimeter.
- Labour is taken as roughly 55% of the installed figure — so the DIY materials-only line is about 45%.
- Excluded: stairs, built-in benches, lighting, pergolas, multi-level framing, permit fees and any ledger or footing work driven by local code.
Worked example
A 16 × 12 ft ground-level Trex deck with railing on three open sides
- Area = 16 × 12 = 192 sq ft
- Decking = 192 × $30 to $60 × 1.0 = $5,760 to $11,520
- Railing = 16 + 2 × 12 = 40 lineal ft × $25 to $60 = $1,000 to $2,400
- Total = $6,760 to $13,920
Result:About $6,760 to $13,920 installed in Trex — roughly $54 per sq ft at the midpoint.
Built and maintained by Christoph Ballmer, Honeygoat GmbH
Method and constants last checked against the calculator code on August 17, 2026. Independent trade review is not yet in place for this calculator — see how we handle review.
Read the site-wide calculation methodology · estimate vs. quote and safety limits
How much does a Trex deck cost?
Trex is the best-known composite decking brand in the US. A Trex deck costs more up front than pressure-treated wood, but the capped composite boards resist rot, fading and stains and need almost no maintenance, which is what draws homeowners to it. The price depends on the Trex line you choose, the deck size and height, and railing.
As an installed all-in figure, Trex decking typically runs $30–$60 per square foot. On a 320 sq ft deck (16×20 ft) that is roughly $9,500–$19,000, before railing and stairs. The estimate above lets you set your size, height and railing to tighten the range.
cost = area × $30–$60/sq ft (× height) + railing length × rail rate
Building it yourself? Size the boards and hardware with the deck board calculator. Hiring out? Compare quotes from local deck builders below.
Deck cost by decking brand
Compare the installed cost of other decking brands:
Frequently asked questions
How much does a Trex deck cost?
Trex composite decking typically runs $30–$60 per square foot installed. On a 320 sq ft deck (16×20 ft) that is roughly $9,500–$19,000, before railing and stairs. Trex is the best-known composite decking brand in the US. Enter your own size above for an estimate.
Is Trex worth the extra cost over wood?
Trex costs more up front than pressure-treated wood, but it resists rot, fading and stains and needs little upkeep, so it can be cheaper over the deck's life. Whether that trade-off is worth it depends on how long you'll keep the deck and how much maintenance you want to avoid.
Which Trex line should I choose?
Trex sells three tiers and the tier moves the price more than the deck size does: Enhance is the entry line at the lower end of the $30–$60 range, Select sits mid-pack, and Transcend is the premium line at the top. All three are capped composite — the difference is the depth of the cap, the grain realism and the warranty length. Price your size above, then move between tiers before deciding.
Does Trex get hot in the sun?
Composite runs hotter underfoot than wood, and dark colors noticeably more than light ones. On a full-sun deck or a pool surround, choose a lighter color, plan shade, and expect midday barefoot comfort to be the real constraint rather than any structural issue. This is a category trait of composite decking, not a Trex-specific flaw.
What maintenance does a Trex deck actually need?
No sanding, staining or sealing — that is the entire pitch. What remains is a soap-and-water wash once or twice a year, keeping the gaps clear so the deck drains and ventilates, and following the installation guide's clearance rules. Mold on composite grows on pollen and dirt sitting on the surface, so the wash is about keeping the food source off, not protecting the board.
Do I need a permit to build a deck?
In most US jurisdictions, yes — any deck attached to the house, or a freestanding deck above a certain height or size (often around 30 inches high or 200 square feet), needs a building permit and at least one inspection. Permit fees commonly run $50 to $500, and larger or engineered decks cost more. Building without a required permit can mean fines, a forced rebuild, or trouble when you sell the home, so check with your local building department before you start.