DIY & materials
Decking boards Calculator
Estimate straight decking rows, board lengths and order quantity. This free decking boards calculator shows the calculation and its assumptions so you can compare your own figures.
Your results
Estimate straight decking rows, board lengths and order quantity.
Calculated outcomes
- Rows
- 28
- Segments Per Row
- 2
- Ordered Linear Metres
- 177
Assumptions and estimates
- Method: Rows = ceiling((deck width + gap) ÷ (board width + gap)). Segments per row = ceiling(deck length ÷ board length).
- Conservative estimate counts full segments per row without reusing offcuts. Joists, posts, fixings, end gaps and structural design are excluded.
Useful next steps
- Use Compare options to test an alternative side by side.
- Copy, print or download a record of this calculation when you need one.
Reports open your email app addressed to s@s1.ie with the public page address only. Your inputs are never added.
How the decking boards calculation works
Rows = ceiling((deck width + gap) ÷ (board width + gap)). Segments per row = ceiling(deck length ÷ board length).
Conservative estimate counts full segments per row without reusing offcuts. Joists, posts, fixings, end gaps and structural design are excluded.
Using this calculator
- Enter your own figures in the labelled inputs. Keep the currencies, units and time periods consistent.
- Choose any applicable rate profile, pattern or assumption shown for this tool. Open additional inputs when relevant.
- Review boards and material cost, then read the stated assumptions and eligibility conditions before using the result.
Worked example
This is a static example using illustrative inputs, not facts about you or today’s date. The displayed eligibility selections and assumptions apply only to this example.
See example inputs
- Deck length along boards (m)
- 5
- Deck width across boards (m)
- 4
- Board width (mm)
- 140
- Board gap (mm)
- 5
- Available board length (m)
- 3
- Extra waste allowance (%)
- 5
- Board price (€)
- 18
- Boards
- 59
- Material Cost
- €1,062.00