How to Calculate Insulation
What is Insulation?
An insulation calculator estimates the amount of insulation material (rolls, batts, or loose fill) needed for walls, loft/attic, or floor, and the expected energy savings or U-value improvement.
Step-by-Step Guide
- 1Calculate area to be insulated (m²)
- 2Determine required R-value or U-value based on building regulations and climate zone
- 3Select insulation type: mineral wool, PIR foam, cellulose, spray foam
- 4Quantity = area / coverage per roll or bag (listed on product label)
Worked Examples
Input
Loft 50m² · 270mm mineral wool to achieve Part L compliance
Result
~6 rolls (large rolls cover 8.5m²)
UK Part L requires ~0.16 W/m²K for lofts
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