Deck Calculator
A deck calculator estimates the decking boards, joists, posts, and fixings needed to build a timber or composite deck. It also estimates the total cost based on material choice.
- 1Calculate deck area (length × width)
- 2Board count: area ÷ (board width − gap) × board length; add 10% for diagonal or waste
- 3Joist spacing: typically 400mm centres; number = deck length ÷ 0.4 + 1
- 4Posts: typically every 1.5–2m where frame meets ground
4m × 3m deck · 140mm×28mm boards at 5mm gap=~20 boards at 4m length3m ÷ 0.145 = 20.7 runs
⭐
Fun Fact
Composite decking (wood-plastic) costs 2–3× more upfront than treated softwood but has a lifespan of 25+ years vs 10–15 years for softwood, making it often cheaper long-term.
References
🔒
100% Gratis
Ingen registrering
✓
Nøyaktig
Verifiserte formler
⚡
Øyeblikkelig
Resultater med én gang
📱
Mobilevennlig
Alle enheter