March 25, 2026
A 20×20 deck covers 400 square feet of outdoor living space. In 2026, most homeowners pay $6,000 to $24,000 for a deck this size. The final price depends on three things: material choice, deck type, and labor costs in your area. This guide breaks down the real numbers so you can budget with confidence.
Disclosure: This guide is published by COOWIN, a manufacturer of composite decking materials. We have a commercial interest in composite products. To maintain objectivity, all pricing data in this article comes from independent, third-party sources. Where we reference our own products, we label them clearly.
Capped with an HDPE layer, Capped Composite Decking is made excellent at resisting stains, scratches, weathering, and fading.
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| Deck Size (ft) | Square Feet | Estimated Installed Cost |
|---|---|---|
| 8×10 | 80 | $2,400 – $4,800 |
| 10×10 | 100 | $3,000 – $6,000 |
| 10×12 | 120 | $3,600 – $7,200 |
| 12×12 | 144 | $4,300 – $8,600 |
| 12×16 | 192 | $5,800 – $11,500 |
| 12×20 | 240 | $7,200 – $14,400 |
| 16×16 | 256 | $7,700 – $15,400 |
| 14×20 | 280 | $8,400 – $16,800 |
| 20×20 | 400 | $6,000 – $24,000 |
| 20×24 | 480 | $14,400 – $28,800 |
| 24×24 | 576 | $17,300 – $34,600 |
Sources: HomeGuide (Feb 2026), NerdWallet (Jan 2026), Angi (Mar 2026). Costs assume a standard attached deck on a single-story home using pressure-treated wood at the low end and composite or hardwood at the high end.
The wide range for a 20×20 deck reflects material differences. A basic pressure-treated pine deck starts around $6,000. A premium composite or exotic hardwood deck can exceed $24,000.
The table below shows installed costs per square foot for a standard attached deck on a single-story home.
| Material | Installed Cost (per sq ft) | Lifespan | Annual Maintenance |
|---|---|---|---|
| Pressure-treated pine | $25 – $50 | 10 – 15 years | Stain & seal yearly |
| Cedar | $30 – $47 | 15 – 20 years | Reseal yearly |
| Redwood | $28 – $54 | 20 – 25 years | Reseal yearly |
| Bamboo | $27 – $52 | 15 – 25 years | Periodic sealing |
| Mahogany | $30 – $57 | 25 – 40 years | Reseal every 1–2 years |
| Composite | $40 – $80 | 25 – 50 years | Occasional washing |
| Tigerwood | $40 – $64 | 25 – 30 years | Annual oiling |
| Ipe (Brazilian hardwood) | $50 – $70 | 40 – 70 years | Annual oiling |
| Aluminum | $100 – $125 | 30+ years | Minimal |
On a tight budget? Pressure-treated pine is the most affordable option. It resists rot and insects through chemical treatment. The trade-off: it requires annual staining and sealing to stay in good shape. Expect to spend $1.50 to $4 per square foot each year on maintenance.
Want low maintenance? Composite decking costs more upfront but saves money over time. It won’t crack, warp, or fade from UV exposure. You never need to stain or seal it. Most brands offer 20 to 50-year warranties.
Building for the long haul? Ipe is the gold standard of decking wood. It’s extremely dense and naturally resists mold, insects, and water. An Ipe deck can last 40 to 70 years. The downside: it’s difficult to cut and install, which increases labor costs.
Want natural beauty without the premium price? Cedar and redwood are mid-range options. Both naturally resist insects and weather damage. Cedar absorbs stain beautifully but dents easily due to its softness. Redwood is stronger and resists warping, but it needs annual resealing to prevent mold.
Upfront cost tells only part of the story. Maintenance, repairs, and potential replacement change the math over time.
| Material | Initial Cost (20×20) | 20-Year Maintenance | Replacement Cost | 20-Year Total |
|---|---|---|---|---|
| Pressure-treated pine | $10,000 – $20,000 | $12,000 – $16,000 | $12,000 – $25,000 (at year 15) | $34,000 – $61,000 |
| Cedar | $12,000 – $18,800 | $10,000 – $14,000 | May need replacement at year 18–20 | $22,000 – $42,000 |
| Composite | $16,000 – $32,000 | $1,000 – $2,000 | None needed | $17,000 – $34,000 |
| Ipe | $20,000 – $28,000 | $3,000 – $5,000 | None needed | $23,000 – $33,000 |
Key takeaway: Composite and Ipe decks cost more upfront but are often cheaper over 20 years. A pressure-treated pine deck that needs full replacement at year 15 can end up costing nearly twice as much as a composite deck that lasts the full 20 years.
Composite decking prices vary by brand and product line. Trex is the most recognized name in composite decking. Installation costs range from $45 to $70 per square foot. Most Trex products carry a 20 to 25-year warranty.
COOWIN offers composite decking at $35 to $60 per square foot installed. As a manufacturer selling direct, COOWIN can offer factory pricing. This option works best for contractors and larger projects. Smaller residential orders may find it easier to purchase from local retailers.
Other major composite brands include TimberTech, Fiberon, and Azek. Each offers different product tiers and warranty terms. Always compare at least three brands before committing.
For composite decking pricing details, visit our composite decking cost guide.
The style of deck you build has a major impact on price. Elevated decks need stronger foundations. Multi-level decks require custom engineering.
| Deck Type | Installed Cost (per sq ft) | Notes |
|---|---|---|
| Floating / freestanding | $20 – $25 | No railings or deep footings required. Often does not need a permit for decks under 200 sq ft. |
| Ground-level / platform (attached) | $25 – $30 | Less than 30″ high. Railings not required by code in most areas. |
| Elevated (attached) | $30 – $50 | At least 3 ft above grade. Requires reinforced footings and code-compliant railings. |
| Second-story | $50 – $60 | Needs large support columns and engineered connections. Creates a covered porch below. |
| Multi-level | $60 – $100 | Custom engineering required. Adds stairs, railings, and extra support at each level. |
These are the simplest and most affordable options. Because they sit less than 30 inches off the ground, most building codes do not require railings. Costs increase if you need footings below the frost line or reinforced pads for heavy items like a hot tub.
A floating deck sits on the ground without attaching to your house. It typically rests on gravel and concrete blocks. Because it’s separate from the home, many municipalities do not require a building permit for floating decks under 200 square feet. This makes it the most budget-friendly option.
Any deck 3 feet or more above grade needs reinforced concrete footings and code-compliant railings. Expect costs of $30 to $50 per square foot. The foundation work alone can add $1,500 to $3,000 to the project.
Building a second-story deck requires heavy support columns, engineered connections to the house, and a full staircase. The benefit: you get a covered porch underneath. The cost: $50 to $60 per square foot, and sometimes more for complex stair designs.
These are the most expensive options. A multi-level deck requires custom engineering, multiple sets of stairs, railings at every level, and deep foundations. Prices range from $60 to $100 per square foot. This option works best for hillside lots or homes with two or more stories where you want separate zones for dining, lounging, and recreation.
Labor is the largest single expense in most deck projects. It typically accounts for 40% to 60% of the total cost.
| Labor Category | Cost per Square Foot |
|---|---|
| Basic ground-level deck | $15 – $22 |
| Standard elevated deck | $22 – $30 |
| Complex / multi-level deck | $30 – $42 |
| Premium custom build | $40 – $70 |
Sources: Angi (Mar 2026), Ergeon (Feb 2026), Trex Protect (Dec 2025), Bhumi Calculator (Jan 2026).
Beyond the deck itself, these common add-ons and requirements can affect your total budget.
| Item | Cost Range |
|---|---|
| Building permit | $100 – $500 |
| Structural engineer (site assessment + plans) | $100 – $220 per hour |
| Deck drainage system | $1,000 – $4,000 |
| Gravel base (under elevated decks) | $0.85 – $2.80 per sq ft |
| Yard grading / leveling | $500 – $1,000 |
Learn More: How To Install An Under-Deck Drainage System?
| Item | Cost Range |
|---|---|
| Wood or vinyl railings | $20 – $60 per linear foot |
| Composite railings | $30 – $70 per linear foot |
| Cable or glass railings | $60 – $150+ per linear foot |
| Deck stairs | $20 – $30 per sq ft + $80 – $160 for concrete footings |
| Item | Cost Range |
|---|---|
| Deck staining | $1.50 – $4.00 per sq ft |
| Deck painting | $2.00 – $5.00 per sq ft |
| Deck roof / cover | $10 – $60 per sq ft |
| Item | Cost Range |
|---|---|
| Outdoor lighting (per fixture) | $80 – $300 |
| Outdoor electrical outlet | $180 – $350 |
| Ceiling fan installation | $150 – $400 |
| Built-in wood benches | $1,000 – $1,500 |
| Hot tub (in-ground) | $3,000 – $10,000 |
| Outdoor kitchen with built-in grill | $3,000 – $10,000 |
| Gazebo (prefabricated) | $1,450 – $5,570 |
| Gazebo (custom built) | $4,300 – $10,000 |
| Retractable awning | $200 – $6,000 |
Building your own deck can cut costs by 40% to 60%. For a 12×12 pressure-treated pine deck, DIY materials run about $2,000 to $4,000.
However, DIY is only practical for simple, ground-level decks. Here is how to decide:
DIY is a good fit if: the deck is small (under 200 sq ft), ground-level, freestanding, and uses easy-to-work-with wood like pine or cedar. You also need basic carpentry skills and the right tools.
Hire a professional if: the deck is elevated, attached to your house, requires a permit, includes stairs or railings, or uses dense materials like Ipe or composite. Improper structural connections can cause serious safety hazards.
Many municipalities require a licensed contractor for any attached or elevated deck. Check your local building codes before starting a DIY project.
A simple ground-level deck takes 5 to 10 days of construction time. An elevated or multi-level deck takes 2 to 4 weeks. Add at least one week for permit approval. Site preparation, weather delays, and material delivery can extend the timeline further.
Consider replacement if any of the following apply:
Most deck repairs cost $750 to $2,500. A new 20×20 deck runs $6,000 to $24,000, depending on materials. If repairs are frequent and costly, replacement usually makes more financial sense.
Wood and composite decks need at least 6 inches of clearance above the ground. This allows air circulation and prevents moisture damage. Use concrete blocks, deck pedestals, or gravel pads as a base.
Only concrete patios can sit directly on compacted soil. For any other material, some form of elevated support is necessary.
This article draws pricing data from the following independent sources:
All prices are national averages for the United States. Your actual costs will vary based on location, contractor rates, material availability, and project complexity. We recommend getting multiple professional quotes before making any purchasing decisions.
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