DIY & materials · Calculator companion · By K Imports
Decking boards: practical guide
This guide explains how to use the Count.ie decking boards. Estimate straight decking rows, board lengths and order quantity. Follow the inputs, method and worked example below, then compare your own scenario.
Guide written .
Open the Decking boards calculatorWhat to prepare
- Measure the actual space and record every dimension with its unit.
- Check the supplier's pack size, stated coverage and installation instructions.
- Separate the measured requirement from waste, cuts, overlaps and spare material.
Understand the inputs
The calculation method
Rows = ceiling((deck width + gap) ÷ (board width + gap)). Segments per row = ceiling(deck length ÷ board length).
Worked example
Illustrative inputs and their result.
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
Calculated example result
- Boards
- 59
- Material Cost
- €1,062.00
How to interpret the result
The calculated quantity is a planning estimate, not an installation specification. Whole packs and site conditions can change the order; structural or safety-critical work needs appropriate professional guidance.
Compare alternative dimensions or pack sizes without changing the unit basis. Re-measure uncertain areas before buying, and use the manufacturer's instructions to decide a suitable allowance.
Common mistakes to avoid
- Convert millimetres, centimetres and metres before combining measurements.
- Do not add the same waste allowance at both measurement and ordering stages.
- Check irregular shapes, openings, substrate conditions and manufacturer coverage separately.
Assumptions and sources
Conservative estimate counts full segments per row without reusing offcuts. Joists, posts, fixings, end gaps and structural design are excluded.
If your case falls outside this scope, use a more suitable calculator or contact us about an unclear method.