Deck Cost Calculator

How the estimate works

Deck builders price mostly by the square foot of deck surface, with the cost already blending decking boards, the substructure (posts, beams, joists), and labor. The calculator multiplies your deck's area by a national installed range for the material you pick — from about $15–$25 per sq ft for pressure-treated pine up to $40–$80 for exotic ipe — then applies a height factor, because a raised or second-story deck needs taller posts, more bracing, and harder access.

Railing and stairs are priced separately, since they vary so much: railing runs roughly $20–$60 per linear foot installed, and stairs about $150–$300 per step including stringers and footings. Your region then scales the whole thing up or down. The result is an honest low-to-high range, because real deck bids vary that much.

What drives the price

• Material is the biggest lever — composite and PVC cost roughly 2–3× pressure-treated lumber, and ipe more still.
• Size scales nearly linearly: doubling the square footage roughly doubles the decking cost.
• Height and access add framing and labor — an elevated deck costs noticeably more than the same deck on grade.
• Railing and stairs are add-ons that can each add thousands; a fully railed deck with a long stair run is a different budget than an open ground-level platform.

Common mistakes

• Skimping on the ledger and footings. A poorly flashed ledger is the #1 cause of deck collapses — this is not where to save.
• Forgetting railing and stairs. They're easy to leave out of a mental estimate and can add 20–40% to the job.
• Comparing material price without lifetime cost. Wood is cheaper to build but needs staining every few years; composite costs more up front and almost nothing after.
• Taking one bid. Deck bids for the same job routinely vary 30–40%. Always get three.

When this calculator is the wrong tool

Use a pro for: rooftop and structural decks, decks with built-in benches, planters, pergolas, or lighting, multi-level designs, or anything requiring engineered footings on a slope. This tool estimates a standard residential deck.

The formula behind the estimate

The calculator builds your range from four parts, each priced the way contractors actually bid them, then scales the sum by your region. In plain terms:

Total = ( Decking + Railing + Stairs + Demolition ) × Region factor

• Decking + labor = deck area (sq ft) × the material's installed price per sq ft × a height factor. The per-sq-ft figure already blends boards, the substructure (posts, beams, joists), fasteners, and labor, which is how deck guides quote it. The height factor is 1.0 at ground level, 1.2 for a raised deck, and 1.4 for a second-story or elevated deck, reflecting taller posts, extra bracing, and harder access.
• Railing = linear feet × $20–$60 per ft installed. Plain pressure-treated railing sits at the low end; metal balusters, cable, or composite railing at the high end.
• Stairs = number of steps × $150–$300 per step, including stringers, treads, and a footing or landing.
• Demolition (optional) = deck area × $3–$10 per sq ft to tear out and haul away an existing deck of the same size. This one is not height-scaled, because tear-out cost tracks how much old structure comes out, not how tall the new deck will be.

The region factor is 0.85 for lower-cost areas, 1.0 at the national average, and 1.25 for high-cost metros — and the state selector just picks one of those three for you. Each side of the range (low and high) is rounded to the nearest $50, so the result reads like a real bid rather than a false-precision number.

Worked example: a 16×20 composite deck, raised, with stairs

Say you're building a 16×20 ft deck — that's 320 sq ft — in composite (Trex/TimberTech), raised a few feet off the ground, with 48 linear feet of railing, a 5-step stair run, and you're in a national-average cost area. Here's the math the calculator runs:

• Decking + labor: 320 sq ft × $30–$60/sq ft × 1.2 (raised) = $11,520–$23,040
• Railing: 48 ft × $20–$60/ft = $960–$2,880
• Stairs: 5 steps × $150–$300/step = $750–$1,500
• Region factor: ×1.0 (national average)

Add the parts and round to the nearest $50 and you get roughly $13,250 on the low end to $27,400 on the high end, with a midpoint near $20,300. Swap the material to pressure-treated and the decking line drops to about $5,760–$9,600, pulling the whole job down to the $7,500–$14,000 range — a vivid illustration of how much the board choice drives the budget. Add the demolition box for an old 320 sq ft deck and you'd tack on roughly $960–$3,200 more.

Decking materials compared

Material is the single biggest cost lever, and the cheapest board to install is rarely the cheapest to own. Here's how the common choices stack up — installed price, how long they last, and what upkeep they demand:

The takeaway: pressure-treated wins on up-front price but costs you in stain, sealer, and weekends for the life of the deck. Composite and PVC cost roughly two to three times as much to build, then ask almost nothing of you for decades. Over a 25-year horizon the lifetime cost of wood and composite often converge — so pick based on how much maintenance you're willing to do, not just the sticker.

What actually drives the price

Two decks of identical square footage can be thousands apart. The drivers, roughly in order of impact:

• Material — composite/PVC vs pressure-treated is a 2–3× swing on the biggest line item.
• Height and access — a second-story deck needs taller posts, more bracing, and slower work; the calculator's 1.2–1.4 factor captures it.
• Railing — required by code above ~30 inches, and the style (basic wood vs cable or metal) can triple the per-foot cost.
• Stairs — every run adds stringers and a footing or landing; a long descent on a raised deck adds up fast.
• Permits and footings — most attached or raised decks need a permit (often $150–$500) plus an inspected ledger and footings below the frost line. Sloped or poor soil means deeper, pricier footings.
• Demolition — tearing out an old deck first is its own line, especially if footings are set in concrete.

DIY vs hiring a pro

Because labor is often close to half the cost, a confident DIYer can save real money — a ground-level pressure-treated platform is within reach for someone comfortable with a circular saw, a level, and a long weekend. Building it yourself mostly removes the labor portion, leaving materials plus tool rental and permit fees.

The case for hiring out gets stronger as the deck gets taller and more attached to the house. The ledger connection and footings are structural and life-safety critical: a poorly flashed ledger is the leading cause of deck collapses, and a botched footing can heave a deck out of level in one winter. If the deck is raised, attached, or carries a railing by code, the cost of a pro is cheap insurance — and many jurisdictions require permitted, inspected work regardless of who swings the hammer. A reasonable middle path is to DIY a simple low platform and hire out anything elevated or structural.

Sources & how we keep this current

The per-square-foot ranges and add-on costs in this tool are compiled from public U.S. home-improvement cost data and reviewed periodically:

• Remodeling's Cost vs. Value report — for deck resale-value recovery and regional cost spread on wood vs composite deck additions.
• HomeAdvisor / Angi cost guides — for national installed-cost ranges by material, plus railing, stairs, and demolition line items.
• Manufacturer data (Trex, TimberTech) — for composite and PVC pricing, lifespan, and maintenance claims.
• Fixr and contractor bid data — to sanity-check the low-to-high spread against what homeowners actually pay.

These are national averages, and deck bids for the very same job routinely vary 30–40% between contractors. Treat the result as a planning range to budget and compare quotes against — then get three written bids from licensed local deck builders before you commit. The underlying figures were last reviewed in mid-2026.