Roof shingle estimator
Roof shingle estimator: calculate a transparent estimate from the values and assumptions you provide.
Your inputs stay in your browser. Displayed results are rounded to a maximum of 12 significant digits.
Method and assumptions
Method version 1.0.0 · Updated
Calculate
Formula: ⌈area × (1 + allowance) / coverage per pack⌉
Roof shingle estimator: calculate a transparent estimate from the values and assumptions you provide.
- roofArea
- Actual roof area (m²)
- wastePercent
- Cutting allowance (%)
- coveragePerPack
- Coverage per pack (m²)
Pitch, overlaps and local requirements may change the actual quantity.
Calculate with code
These short examples use the same inputs and core calculation as this tool. Adapt validation and formatting to your application.
JavaScript
const packs = Math.ceil(90 * 1.10 / 3); // 33