Contractor field notes
Estimate decking boards and a construction cost allowance
Convert the deck footprint into a whole-board allowance using the coverage per board you enter. Add framing and labor rates against the original footprint to develop a preliminary deck cost.
Deck quantity and allowance formulas
Deck area = length × width. Boards = area × (1 + waste percentage ÷ 100) ÷ board coverage, rounded up. Total = boards × board price + area × framing rate + area × labor rate.
Worked example
A 20 ft × 12 ft deck covers 240 sq ft. With 10% waste and 5 sq ft coverage per board, round 264 ÷ 5 = 52.8 up to 53 boards. At $25 per board, $8 framing per sq ft, and $12 labor per sq ft, cost is $1,325 + $1,920 + $2,880 = $6,125.
Common estimating pitfalls
- This is not a structural design or a joist, beam, and footing takeoff.
- Stairs, railing, fasteners, permits, and site-specific requirements are not automatically priced.
Frequently asked questions
How do I find coverage per decking board?
Use the board dimensions and installation spacing or the manufacturer’s stated effective coverage. Nominal width may not equal installed coverage.
Does this design the deck framing?
No. The framing value is a dollar allowance per square foot. Structural sizing and code compliance require separate design and review.
Is the output a customer selling price?
No. It totals the entered decking, framing, and labor allowances. Add other costs, overhead, and an appropriate profit target before quoting.