How much does a composite deck cost per square foot?

Composite decking material costs $3–$12 per square foot for materials alone, and installed composite decks typically run $15–$35 per square foot total including framing, fasteners, and labor. Premium brands like Trex Transcend or TimberTech AZEK push toward the higher end. The higher upfront cost versus pressure-treated lumber is usually recouped over 10–15 years through avoided maintenance costs.

Does adding a deck require a permit?

Yes, in virtually every jurisdiction. Decks are structural additions and require a building permit, inspection, and in many areas an engineering review if the deck is elevated. Freestanding ground-level decks (under 30 inches from grade) may be exempt in some municipalities, but attached decks almost universally require a permit. Unpermitted decks create problems at resale and may need to be removed or retroactively permitted.

What's the cheapest deck material?

Pressure-treated pine is the least expensive deck material, costing $1.50–$3.50 per linear foot for decking boards. An installed PT pine deck runs $8–$18 per square foot all-in. The trade-off is maintenance: PT wood requires annual cleaning and every 2–3 year sealing or staining to prevent cracking, checking, and weathering. Over a 15-year period, composite often costs less in total maintenance-adjusted dollars.

How long does a wood deck last compared to composite?

A pressure-treated wood deck lasts 15–25 years with consistent maintenance; cedar lasts 20–30 years. Composite decking from major manufacturers carries product warranties of 25–50 years against fading, staining, and structural failure, and realistically lasts 30+ years in most climates. Composite boards themselves are highly durable; the frame (joists, posts, beams) is still wood and remains the structural vulnerability in any deck.

Should I repair or replace my existing deck?

Replace when the structural frame — posts, beams, or joists — shows rot, significant deterioration, or bounce underfoot. Repair when the frame is sound and damage is limited to surface boards, railings, or stairs. A contractor can probe joists and posts with a screwdriver to test for soft spots during an assessment. Replacing boards on a rotted frame is money wasted; patching a sound frame saves significant cost.

Deck Addition vs. Deck Replacement: Full Cost Guide for 2026

July 13, 2026 · Cost Guide · 7 min read

Adding a new deck costs between $8,000 and $45,000 in 2026, with the average 300–400 sq ft deck using pressure-treated lumber landing around $12,000–$20,000 fully installed. Replacing an existing deck runs $5,000–$25,000 depending on whether the frame can be reused. The single biggest cost driver isn't size — it's material choice. Composite and PVC decks cost two to three times more than pressure-treated wood per square foot but eliminate annual maintenance and last significantly longer.

New Deck Addition vs. Deck Replacement: Which Do You Actually Need?

The distinction matters for budgeting:

New deck addition: You're adding a deck where none existed. The full cost of excavation (if needed), footings, posts, framing, decking, railings, and stairs is on the table.
Deck replacement (full): Tearing out an existing deck — including the frame — and building new. Comparable cost to a new addition since all structural work is redone.
Deck replacement (decking only): Replacing surface boards while keeping an existing sound frame. Significantly cheaper — typically $3,000–$12,000 — because the structural work is already done.
Deck repair: Replacing damaged boards, railings, or stairs without full deconstruction. Often $1,000–$5,000 depending on scope.

The key diagnostic question: Is your existing frame structurally sound? A contractor can assess this by probing posts and joists with a screwdriver to test for soft spots indicating rot. If the frame is solid, you can often save $8,000–$15,000 by replacing only the surface materials.

Deck Cost by Material Type

Pressure-Treated Pine

Material cost: $1.50–$3.50 per linear foot for decking boards
Installed cost: $8–$18 per square foot
300 sq ft deck total: $8,000–$15,000

Pressure-treated (PT) pine is the entry-level option — affordable upfront, widely available, and used by the majority of deck contractors. The trade-off is maintenance: PT wood requires cleaning annually and resealing or staining every 2–3 years. Skipping maintenance leads to cracking, checking (surface splits), and eventual rot. PT decks also take 6–12 months to dry out enough after installation to accept stain without peeling.

Cedar and Redwood

Material cost: $3–$7 per linear foot
Installed cost: $15–$25 per square foot
300 sq ft deck total: $12,000–$22,000

Cedar and redwood are naturally rot-resistant and contain tannins that deter insects. They have better dimensional stability than PT pine — less warping and checking. They still require periodic sealing but hold up better if maintenance is inconsistent. Regional availability varies: cedar is widely available in the Pacific Northwest and upper Midwest; redwood primarily in California.

Composite Decking

Material cost: $3–$12 per linear foot for boards
Installed cost: $15–$35 per square foot
300 sq ft deck total: $15,000–$30,000

Composite decking is manufactured from a blend of wood fiber and recycled plastic. Leading brands include Trex, TimberTech, Fiberon, and Deckorators. Modern composites look substantially more like natural wood than earlier generations, resist fading and staining, and require minimal maintenance — annual cleaning with soap and water. The structural frame is still wood (pressure-treated); only the surface boards are composite.

Product tiers within composite:

Entry-level composite (Trex Select, Fiberon Horizon): $3–$5/linear ft. Less realistic wood appearance; limited color options; adequate warranty (25 years).
Mid-range (Trex Enhance, TimberTech Pro): $5–$8/linear ft. Better appearance, more color options, improved stain resistance.
Premium (Trex Transcend, TimberTech AZEK): $8–$12/linear ft. Most realistic appearance, dual-sided boards, 50-year warranty against fading and staining.

PVC Decking

Material cost: $7–$14 per linear foot
Installed cost: $20–$40 per square foot
300 sq ft deck total: $18,000–$35,000

100% PVC decking contains no wood fiber, making it completely immune to moisture-related deterioration and impervious to mold, mildew, and insect damage. AZEK by TimberTech is the dominant brand. PVC expands and contracts more than composite in temperature extremes (important in climates with significant seasonal swings), and it has a slightly hollow sound underfoot that some homeowners notice. Best suited for coastal environments or wet climates where moisture resistance is paramount.

Tropical Hardwood (Ipe, Tigerwood, Cumaru)

Material cost: $5–$15 per linear foot
Installed cost: $20–$45 per square foot
300 sq ft deck total: $18,000–$40,000

Tropical hardwoods like ipe (ironwood) are exceptionally dense, naturally resistant to rot and insects, and have a distinctive appearance that weathers to a silver-gray without treatment. They require no sealing for structural protection (though oiling maintains appearance), and properly cared for ipe decks can last 50–75 years. The drawbacks: high material cost, difficult to work with (requires special hardware), sustainability concerns about sourcing, and very limited contractor experience in some regions.

Cost by Deck Size

Size is a straightforward multiplier on per-square-foot costs, but there are diminishing returns on certain fixed costs:

Small deck (100–200 sq ft): $6,000–$18,000 — fixed costs for footings, permitting, and setup represent a higher percentage of the total
Standard deck (200–400 sq ft): $10,000–$30,000 — the most common range for single-family homes
Large deck (400–600 sq ft): $18,000–$45,000+
Multi-level deck: Add $4,000–$12,000 per additional level for structural complexity

What Drives the Price Up Beyond Material and Size

Elevation: Elevated decks (second-story or high off grade) require taller posts, more robust footings, and often structural engineering review. Add $3,000–$8,000 for a deck over 8 feet off grade.
Stairs: Each stair run adds $1,000–$3,500 depending on height, width, and railing requirements.
Railings: Code-required for decks more than 30 inches off grade. Wood railings are least expensive ($50–$100 per linear foot installed); aluminum balusters with composite rails run $100–$200/LF; glass panel railings run $200–$400/LF.
Integrated features: Built-in benches ($150–$350 per linear foot), pergolas ($3,000–$10,000 attached to deck), built-in planters, under-deck drainage systems.
Footings: Most decks require concrete footings below the frost line. Footing depth requirements vary by climate — in northern states, footings may need to extend 36–48 inches. Cost: $300–$800 per footing; most decks need 4–8.
Demolition: Tearing out and disposing of an existing deck adds $1,500–$4,000 to a replacement project.

Does a Deck Add Value? ROI in 2026

The Remodeling Magazine Cost vs. Value Report for 2025 shows wood deck additions returning approximately 72% of project cost at resale; composite deck additions return around 64%. These are national averages — deck ROI varies significantly by climate and local buyer preferences. In warm-weather markets (Texas, Florida, the Southwest), outdoor living space commands a premium. In northern climates with short outdoor seasons, the return is lower.

Condition matters more than material for resale. A well-maintained PT wood deck beats a neglected composite deck every time. Buyers and inspectors look for level decking, secure railings, and absence of rot — not brand names.

For a broader view of which exterior projects pay off most at resale, see our home exterior renovation cost guide and our analysis of which home renovations have the best ROI.

Permits and the Inspection Process

Pulling the permit yourself is possible in some jurisdictions, but most contractors handle this as part of their service. What to expect:

Application: Typically requires site plan showing deck dimensions, distance from property lines, and attachment point to the house
Inspections: Usually two — a footing inspection before concrete is poured, and a final inspection when framing and decking are complete
Fees: $50–$500 depending on jurisdiction and project value
Timeline: 1–3 weeks for permit approval in most markets; some urban jurisdictions run longer

Our home renovation permits guide covers what unpermitted work means for your homeowner's insurance and future sale.

Finding and Vetting a Deck Contractor

Deck work is performed by general contractors, dedicated deck builders, and some landscape contractors. Deck-specialist companies often have deeper product knowledge and more installation experience with specific materials — particularly composite, where installation technique (fastener type, expansion gaps, end cuts) affects long-term appearance and warranty coverage.

Get three quotes minimum and ask each contractor:

Are you a certified installer for the composite or PVC product you're recommending? (Manufacturer certification matters for warranty coverage)
Who pulls the permit, and is that included in your quote?
What's the warranty on your workmanship separate from the product warranty?
What does your framing system look like? (Proper joist sizing, blocking, and ledger attachment are where deck failures originate)

If you're financing the project, see our home renovation financing guide for how HELOCs, home equity loans, and personal loans compare for outdoor projects like decks. Browse home remodeling contractors by city or find verified deck builders near you to compare profiles and project histories.

Frequently Asked Questions

How much does a composite deck cost per square foot?: Composite decking material costs $3–$12 per square foot for materials alone, and installed composite decks typically run $15–$35 per square foot total including framing, fasteners, and labor. Premium brands like Trex Transcend or TimberTech AZEK push toward the higher end. The higher upfront cost versus pressure-treated lumber is usually recouped over 10–15 years through avoided maintenance costs.
Does adding a deck require a permit?: Yes, in virtually every jurisdiction. Decks are structural additions and require a building permit, inspection, and in many areas an engineering review if the deck is elevated. Freestanding ground-level decks (under 30 inches from grade) may be exempt in some municipalities, but attached decks almost universally require a permit. Unpermitted decks create problems at resale and may need to be removed or retroactively permitted.
What's the cheapest deck material?: Pressure-treated pine is the least expensive deck material, costing $1.50–$3.50 per linear foot for decking boards. An installed PT pine deck runs $8–$18 per square foot all-in. The trade-off is maintenance: PT wood requires annual cleaning and every 2–3 year sealing or staining to prevent cracking, checking, and weathering. Over a 15-year period, composite often costs less in total maintenance-adjusted dollars.
How long does a wood deck last compared to composite?: A pressure-treated wood deck lasts 15–25 years with consistent maintenance; cedar lasts 20–30 years. Composite decking from major manufacturers carries product warranties of 25–50 years against fading, staining, and structural failure, and realistically lasts 30+ years in most climates. Composite boards themselves are highly durable; the frame (joists, posts, beams) is still wood and remains the structural vulnerability in any deck.
Should I repair or replace my existing deck?: Replace when the structural frame — posts, beams, or joists — shows rot, significant deterioration, or bounce underfoot. Repair when the frame is sound and damage is limited to surface boards, railings, or stairs. A contractor can probe joists and posts with a screwdriver to test for soft spots during an assessment. Replacing boards on a rotted frame is money wasted; patching a sound frame saves significant cost.