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Decking Board Calculator

Estimate decking board count from deck area, board dimensions and waste.

Board gaps, frame design, direction, offcuts and board stock lengths affect final quantities.

Notes and next steps

How it works

Estimate decking board count from deck area and board dimensions.

Estimating method: Adjusted deck area = deck area × (1 + waste percentage ÷ 100). Boards = adjusted deck area ÷ board face area, rounded up.

Worked example

12 m² with 10% waste is 13.2 m². A 3.6 m × 0.145 m board covers 0.522 m², so buy 26 boards.

Common mistakes
  • Ignoring board gaps and direction.
  • Forgetting frame/joist materials.
  • Not allowing extra for staggered joins and cuts.
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