Cost to Build a Deck

Building a deck costs $30–$75 per square foot installed in the 2026 US range. A typical 16×20 (320 sq ft) backyard deck lands $9,600–$19,200 in pressure-treated wood and $11,200–$22,400 in composite — footings, framing, boards, railings, and labor included. The spread is not padding; it is mostly material choice, height above grade, and how much stair and railing the design needs. This guide prices a brand-new build. If your existing deck is failing, compare against our deck repair cost guide first — repair sometimes beats a new build, and sometimes it is money poured into a dying frame.

Deck cost per square foot by material

Installed pricing for a standard attached deck on a new substructure, with code railings where height requires them. Materials (footings, framing, boards, fasteners, railings) are roughly half the installed figure on a typical build; labor is the other half.

Two cautions on these bands. First, the per-sq-ft figure falls as decks get bigger — fixed costs like permits, mobilization, and a basic stair run spread over more area — so a small deck prices high per foot and a large one lower. Second, material is a lifetime decision, not just a build price: wood is cheapest to build and most expensive to own (stain or seal every 2–3 years), while composite trades a higher build price for near-zero upkeep. The full tier-by-tier breakdown is in our composite deck cost guide.

Cost by deck size

Installed totals at 2026 pricing for ordinary attached decks with a new substructure, basic railing, and a simple stair run where height requires one.

Ground-level platforms can land below these bands (less framing, no railing, no stairs). Second-story, multi-level, or wraparound designs land above them. For a hard reference point, the 2025 Zonda Cost vs Value Report priced a 16×20 composite deck addition at $25,096 nationally — above the mid-range here, reflecting premium finishes — with 88.5% of the cost recouped at resale.

What a deck quote actually includes

A proper deck quote is six line items. If any of them are missing from a bid, they are either buried in the lump sum or coming back as a change order:

• Footings and foundation (~10–15% of total). Concrete footings dug below the frost line, posts, and hardware. Rocky soil, steep grades, and engineered footings for elevated decks push this line up fast.
• Framing (~20–25%). Pressure-treated beams, joists, ledger board and flashing where the deck meets the house. The ledger connection is the most safety-critical joint on the whole structure.
• Decking boards (~20–30%). $3–$9 per linear foot depending on material tier; a 320 sq ft deck uses 650–700 linear feet of board. Our deck board installation guide breaks down the board math.
• Railings (~10–20%). Code-required on decks more than 30 inches above grade. Basic wood or composite rail is the budget option; aluminum and cable systems run $50–$100+ per linear foot.
• Stairs. $200–$500 per step including stringers, treads, and handrail — priced separately in our deck stairs cost guide. A tall deck's stair run is a four-figure line item, not a rounding error.
• Permits, labor, and disposal. Permits run $100–$500; labor overall is roughly half the installed price; and if an old deck comes out first, tear-out adds $3–$5 per sq ft — see deck demolition cost.

Compare bids line by line, not by the bottom number. Two quotes $5,000 apart usually differ in scope — one includes railings, stairs, and permits, the other discovers them later.

What moves the price

• Material. The biggest single lever: the same 320 sq ft footprint is a $9,600 wood deck or a $25,600 PVC deck.
• Height above grade. Ground-level platforms are framing-lite. Every foot of elevation adds post, beam, bracing, and stair cost; second-story decks routinely add $10–$20 per sq ft.
• Design complexity. Rectangles are cheap. Angles, curves, multiple levels, and diagonal board patterns multiply cuts, waste, and labor.
• Stairs and railings. Together they can reach a third of an elevated deck's price — and they are the lines most often lowballed in a first quote.
• Site and access. Tight side yards, slopes, and hand-carried materials slow everything down. Grading or drainage work adds thousands on bad lots.
• Region and season. Labor markets move totals 20–30% between regions, and spring bookings price higher than late-fall ones in most of the country.
• Extras. Built-in seating, lighting ($500–$2,000), pergolas, and under-deck drainage ($3–$8/sq ft) are each priced on top of the base build.

Permits, codes, and inspections

Most jurisdictions require a permit for attached decks and for any deck more than 30 inches above grade or larger than 200 sq ft — the exact triggers are local, so check before you design around them. Budget $100–$500 for the permit and expect two or three inspections: footings before the pour, framing before the boards go down, and a final once railings and stairs are in. Setback rules, lot-coverage limits, and HOA approvals can all constrain size and placement even when a permit is straightforward.

Skipping the permit is the most expensive saving in this category. An unpermitted deck surfaces at resale (and can force removal), weakens insurance claims if anyone is hurt on it, and is built without the footing and ledger inspections that catch the failures decks are known for. The permit is the cheapest structural insurance on the project.

DIY vs. hiring a pro

DIY materials for a wood deck run $15–$25 per sq ft (composite $20–$35), so building it yourself saves roughly 40–50% against the installed price — a 320 sq ft wood deck is about $5,000– $8,000 in materials against $9,600–$19,200 hired out. That saving buys real obligations: the structure carries people, footings must reach below frost, the ledger must be flashed and bolted correctly, and permits and inspections apply to homeowner-builders too. Add tool purchases or rentals and 3–6 weekends of work.

The hybrid route splits the difference and is what many contractors quietly recommend: hire out the footings and framing (the structural, inspection-heavy part), then lay boards and build the railing yourself (the visible, forgiving part). Whichever route you take, price the material list first — our deck board calculator works out boards, and the deck & fence calculator covers posts, framing, and the full estimate.

Ways to keep the cost down

• Build a rectangle at grade. The single cheapest design decision: no angles, minimal railing, no long stair run.
• Choose pressure-treated boards now, upgrade later. The frame is the permanent part; boards can be swapped for composite in 10–15 years when the budget recovers.
• Get three itemized quotes. Identical scope, line by line — the spread between bids on the same deck is routinely 25–40%.
• Book off-season. Late fall and winter slots are discounted in most markets and come with shorter waits.
• Plan the extras before signing. Lighting, drainage, and seating added mid-build are priced as change orders — always the expensive way to buy them.
• Do the demolition yourself. Tearing out an old deck is unskilled labor at $3–$5 per sq ft; a weekend of it can save $1,000+.

When you're ready to turn these ranges into your number, run the deck & fence calculator for a material-level estimate, then compare it against contractor bids in a proper quote — if a bid lands far outside the ranges above, the scope is different, not the market.