Deck Calculator – Lumber and Materials
Calculate lumber, decking boards, and fasteners needed for any deck.
About This Calculator
Calculate lumber, decking boards, and fasteners needed for any deck. Use the calculator above for instant results.
Worked Examples
- Area: 240 sq ft | Boards: 27 | Lineal ft: 540ft
- With 10% waste: 30 boards
Answer: 30 boards / 540 lineal ft
- Area: 192 sq ft | Boards: 27 | Lineal ft: 432ft
Answer: 27 boards
- 100 sq ft | 22 boards
Answer: 22 boards
Who Uses This Calculator?
Estimate lumber for deck bids.
DIY deck material estimate.
Help customers calculate needs.
Plan deck construction project.
Common Mistakes to Avoid
❌ Not accounting for board gaps
Gaps allow water drainage and wood expansion. Factor 1/8 inch gap per board.
❌ Forgetting structural lumber
Decking boards are just the surface. Posts, joists, beams, and hardware add significant cost to total project.
Frequently Asked Questions
Composite vs wood?
Composite: more expensive upfront, virtually no maintenance. Pressure-treated wood: cheaper, needs annual sealing.
Deck permit required?
Most jurisdictions require permits for decks over 30 inches from ground or attached to the house. Always check local code.
Joist spacing?
Standard: 16 inches on center. For diagonal decking: 12 inches on center. Composite may require 12 inch spacing.