Decking Calculator: Estimate Materials & Costs
Planning a new deck? Estimate how many boards, screws, and joists you need for your DIY project with material cost projections and a full material list.
How to Use This Decking Calculator
- Enter the length and width of your deck area.
- Select your board size and spacing.
- Click "Calculate" to see your material list and cost estimate.
- Add 10-15% to your total for waste and cuts.
Full DIY Material List & Planning Notes
Planning a deck requires budgeting for boards, subframe joists, and hardware fixings:
- Decking Boards: Accounts for your effective board width and gap, adding a 10% allowance for cutting, squaring, and offcuts.
- Subframe Joists: Standard timber decking uses 400mm on-center joist spacing (300mm for composite).
- Fixings & Screws: Allow 2 exterior screws at every joist intersection (approx. 20–25 screws per m²).
- Cost Projections: Pressure-treated pine typically costs $25–$50/m²; composite decking ranges from $75–$110+/m².
📖 Complete In-Depth Guide
The Ultimate DIY Decking Guide: How to Estimate Materials Like a Pro
Learn how to measure your decking area accurately, calculate board quantities, plan joist spacing, and factor in waste to save money and avoid project delays.
Read the Full Guide →🧭 What's Your Next Decision?
- 🧱 Estimating masonry or bricks? → Brick Calculator
- 🪵 Planning patio or decking timber? → Decking Calculator
- 📐 Measuring surface or floor area? → Square Footage Calculator
- 🏗️ Pouring footings, slabs or foundations? → Concrete Calculator