Deck Cost Calculator (By Size & Material)
Calculate deck construction costs by size and material (wood or composite) with labor, railing, stairs, and extras included.
Estimated Total Cost
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How Much Does It Cost to Build a Deck?
The average cost to build a new deck ranges from $4,000 to $15,000, depending on the size, materials, and complexity. Pressure-treated wood is the most affordable option at $15–25 per square foot installed, while composite decking typically runs $30–45 per square foot.
Factors That Affect Deck Cost
- Material choice — The single biggest factor. Composite costs 2–3x more than pressure-treated lumber but lasts longer and requires less maintenance.
- Deck size — Most residential decks range from 200–500 sq ft. Larger decks benefit from economies of scale on labor.
- Elevation and stairs — Raised decks and stair sets add structural complexity and cost.
- Railing — Wood railing costs $20–35 per linear foot. Aluminum or cable railing can cost $50–100+.
- Permits — Most municipalities require a building permit for decks, typically $200–500.
Deck Material Comparison
| Material | Cost/sq ft | Lifespan | Maintenance |
|---|---|---|---|
| Pressure-Treated Wood | $15–25 | 10–15 years | Stain/seal every 2–3 years |
| Cedar | $25–35 | 15–20 years | Seal every 3–5 years |
| Composite | $30–45 | 25–30 years | Minimal — wash annually |
| Tropical Hardwood | $40–60 | 25–40 years | Oil annually |
Frequently Asked Questions
How much does it cost to build a 12x12 deck? +
A 144 sq ft pressure-treated wood deck typically costs $3,500–$6,000 installed. The same size in composite decking (like Trex) runs $6,000–$10,000. Prices include basic framing, decking boards, and a standard stair but exclude custom railings, built-in seating, or pergolas.
Is composite or wood decking cheaper? +
Pressure-treated wood is cheaper upfront — roughly $15–25 per sq ft installed vs. $30–60 for composite. But wood requires annual sealing or staining and replacement after 15–20 years. Composite costs 2–3x more initially but needs almost no maintenance and lasts 25–30+ years. Most homeowners find composite cheaper over a 20-year horizon.
Do I need a permit to build a deck? +
Usually yes. Most municipalities require a building permit for decks attached to the house or over a certain size (often 200 sq ft or 30 inches off the ground). Freestanding ground-level decks under 200 sq ft may be exempt. Always check with your local building department before starting — unpermitted decks can complicate home sales.
How long does a deck last? +
Pressure-treated pine decks last 15–25 years with regular maintenance (annual cleaning, sealing every 2–3 years). Cedar and redwood last 20–25 years. Composite decking typically lasts 25–30+ years with minimal upkeep. Concrete footings and hardware usually outlast the decking itself.