← Back
🏗️ Deck Cost Calculator
Estimate Your Deck Building Cost
✅ Formula verified against standard references
•
Last Updated: Jan 2026
sq
ft
Typical: 200-400 sq ft
linear
ft
$22-35/sq ft
💡 Pro Tips from Steve Morrison
- Composite pays off if you stay 10+ years: $12k composite deck vs $7k pressure-treated. PT needs staining every 3 years ($800). Over 15 years: PT costs $11k ($7k + 5 stainings). Composite: still $12k, zero maintenance. Break-even year 12.
- Size sweet spot is 300-400 sq ft: Under 200 sq ft, fixed costs (permits, foundation, stairs) make per-sq-ft cost $40-50. At 300 sq ft, cost drops to $25-35/sq ft. Going bigger than 500 sq ft doesn't save much more—only 10-15% cheaper per sq ft.
⚠️ Common Mistakes
- Comparing materials on price alone: PT wood $7k vs composite $12k. But PT needs $800 staining every 3 years. Over 15 years PT costs $11k total. Composite still $12k with zero maintenance.
- Underestimating permit/inspection costs: Deck quote is $10k. Forgot $400 permit, $600 electrical for lights, $800 railing upgrade to code. Real cost $11,800.
- DIY to "save 50%": Materials are 60% of cost, not 30%. You save labor ($4k) but spend 60 hours + tool rental ($500). Only worth it if your time is free.