Insulation Calculator
By Miikka · CalcBrew · Updated
12 packages
Packages needed
| Area | 538 sq ft |
| +5% waste | 565.1 sq ft |
| Packages | 12 packages |
This insulation calculator estimates how many packages of mineral wool you need to insulate a wall or ceiling. Enter the area to be insulated and the coverage of one package to get the number of packages with waste included.
How the calculator works and what it’s for▾
How the calculator works
The tool divides the area to be insulated by the coverage of one package and rounds the result up to whole packages. It also adds a 5% waste margin to the area to allow for fitting and trimming.
If you insulate 40 m² of wall and one package covers 5 m², you will need roughly nine packages once waste is counted in.
Inputs and results
Enter the area in square metres and the coverage per package in square metres. The result shows the area, the area increased by the waste margin, and the number of packages needed.
The package count is rounded up, so the figure is ready for your shopping list.
Who it is for
It suits renovators and self-builders insulating walls, partitions or ceilings. It helps you avoid both extra trips to the store and a large surplus.
Good to know
Coverage per package is printed on the product packaging, stating how many square metres a package covers at a given thickness. Always check the right value, since coverage varies with the type of wool and the insulation thickness.
🔄 Reviewed June 2026
Frequently asked questions
Cite this calculator
CalcBrew. (2026). Insulation Calculator. https://calcbrew.com/insulation-calculator“Insulation Calculator.” CalcBrew, 2026, calcbrew.com/insulation-calculator.Link to https://calcbrew.com/insulation-calculator. Results are estimates; cite the underlying formula or data source for academic work.
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