What is the average cost to build a deck?

The average cost to build a 400 sq ft deck ranges from $8,000–$20,000 for pressure-treated wood construction and $16,000–$36,000 for composite decking. High-end custom decks with multiple levels, built-in seating, pergolas, and outdoor kitchens can exceed $75,000. Cost per square foot ranges from $20–$45 for basic wood to $40–$90 for composite or hardwood.

Is composite decking worth the extra cost?

For most homeowners, yes. Composite decking costs 30–60% more upfront than pressure-treated wood but requires virtually no maintenance — no annual staining or sealing, no splintering, and typically 25+ year product warranties. Over a 20-year horizon, the total cost of ownership for composite is often lower than wood when you factor in maintenance costs.

Do I need a permit to build a deck?

In most jurisdictions, yes — any attached deck requires a building permit. Permits verify that the deck's structural connections, footings, and railings meet code (especially important for elevated decks). Detached ground-level platforms may be exempt depending on local rules, but check with your building department before starting.

Deck Building Cost Guide 2026: What to Expect Per Square Foot

May 30, 2026 · Cost Guide · 3 min read

Deck Costs at a Glance (2026)

Building a new deck is one of the most popular home improvement projects — and one of the highest-ROI ones. The national average return on investment for a wood deck addition is around 65–70% at resale, while composite decks often recoup 60–65%. Here's what to expect to pay in 2026.

Cost by Decking Material

Pressure-Treated Wood

The most affordable option. Pressure-treated (PT) lumber is chemically treated to resist rot and insects and is widely available. Typical cost: $20–$35 per sq ft installed for a straightforward deck. Requires staining or sealing every 2–3 years and may warp or splinter over time. Lifespan with maintenance: 15–25 years.

Cedar and Redwood

Naturally rot-resistant, attractive appearance, fewer splinters than PT. Cost: $30–$50 per sq ft installed. Requires similar maintenance to PT lumber. Less available than PT in many markets, which drives up cost.

Composite Decking

Made from wood fiber and recycled plastic. Industry leaders include Trex, TimberTech, and Azek. Cost: $40–$75 per sq ft installed depending on brand and product line. Minimal maintenance — annual cleaning only. Warranties up to 25–50 years. Most popular choice for new decks in 2026.

PVC Decking

100% plastic — no wood fiber, completely impervious to moisture. Cost: $50–$90 per sq ft installed. Best for waterfront or very wet climates. Can feel hotter underfoot in direct sun than composite.

Hardwood (Ipe, Tigerwood, Massaranduba)

Exotic hardwoods are among the most beautiful and durable options. Cost: $55–$95+ per sq ft installed. Very hard, dense, and naturally rot-resistant. Requires periodic oiling. Sourcing from certified sustainable forests is important for environmental reasons.

Cost Factors Beyond Materials

Deck Size and Shape

Rectangular decks are least expensive. Complex shapes (L-shape, wraparound, curved) add 20–40% to labor costs due to more intricate framing and more material waste.

Height Above Grade

Ground-level decks are cheapest to build. Every foot of elevation adds structural requirements — larger footings, heavier posts, more extensive framing. Elevated decks over 30 inches also require railings by code ($40–$80 per linear foot for code-compliant railings).

Stairs

Each flight of stairs adds $1,000–$3,000 depending on width and material. Landing areas add further cost.

Built-In Features

Built-in bench seating: $150–$350 per linear foot
Pergola or shade structure: $5,000–$18,000
Outdoor kitchen rough-in: $3,000–$8,000 (for gas, electrical, plumbing)
Deck lighting: $1,500–$5,000 for a fully lit deck

How to Save on Deck Construction

Choose a simple rectangular shape — it's structurally efficient and easy to build
Consider pressure-treated framing with composite decking boards — the framing is hidden, so investing in higher-grade visible boards only makes sense for the top surface
Get at least three bids — deck pricing varies 25–35% between contractors
Build in the off-season (fall/winter) — many contractors offer better pricing and faster scheduling

Find qualified deck contractors by browsing our city-by-city contractor directory.

Frequently Asked Questions

What is the average cost to build a deck?: The average cost to build a 400 sq ft deck ranges from $8,000–$20,000 for pressure-treated wood construction and $16,000–$36,000 for composite decking. High-end custom decks with multiple levels, built-in seating, pergolas, and outdoor kitchens can exceed $75,000. Cost per square foot ranges from $20–$45 for basic wood to $40–$90 for composite or hardwood.
Is composite decking worth the extra cost?: For most homeowners, yes. Composite decking costs 30–60% more upfront than pressure-treated wood but requires virtually no maintenance — no annual staining or sealing, no splintering, and typically 25+ year product warranties. Over a 20-year horizon, the total cost of ownership for composite is often lower than wood when you factor in maintenance costs.
Do I need a permit to build a deck?: In most jurisdictions, yes — any attached deck requires a building permit. Permits verify that the deck's structural connections, footings, and railings meet code (especially important for elevated decks). Detached ground-level platforms may be exempt depending on local rules, but check with your building department before starting.