How much lumber for a 12×14 ft deck?
Answer
58 boards, 12 joists, 8 posts
Deck area: 168 sq ftDecking boards (5.5" wide, 12' long): 58 boardsJoists (16" on center): 12Posts: 8 (2 beams)Screws: 687Linear feet of decking: 400 ftIncludes 10% waste factor
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How We Calculated This
Boards = ceil(rows × boardsPerRow × 1.10), Joists = ceil(width×12 / spacing) + 1
Area = 12 × 14 = 168 sq ft. Boards = 58 (with 10% waste). Joists = ceil(14×12 / 16) + 1 = 12. Posts = 8.
Related Calculations
How much lumber for a 8×10 ft deck?20 boards, 9 joists, 6 postsHow much lumber for a 8×12 ft deck?20 boards, 10 joists, 6 postsHow much lumber for a 10×10 ft deck?25 boards, 9 joists, 6 postsHow much lumber for a 10×12 ft deck?25 boards, 10 joists, 6 postsHow much lumber for a 10×14 ft deck?49 boards, 12 joists, 8 posts
Calculated using verified formulas. Last updated March 2026.