Insulation Calculator
Determine the insulation R-value and thickness needed to meet energy codes for any climate.
Insulation Results
📊 Summary
How it works
R-Value = R-value per inch × Thickness (inches) Climate Zone R-Value Requirements: Zone 1: R-13 Zone 2: R-15 Zone 3: R-19 Zone 4: R-25 Zone 5: R-30 Zone 6: R-38 Zone 7: R-42 Batts Needed = Area (sq ft) / 64 Bags (Cellulose) = Area × Thickness / 140 Example: 1000 sq ft with R-3.2/inch insulation at 3.5" thickness R-Value = 3.2 × 3.5 = R-11.2 Batts = 1000 / 64 = 16 batts
The insulation calculator estimates R-value and material quantities needed for attics, walls, and crawl spaces. Enter area and select insulation type to calculate required R-value, thickness, and number of batts or bags needed. Supports multiple insulation materials with different performance ratings.
Why this matters
Proper insulation reduces heating and cooling costs by 10-30%. Understanding R-values ensures you meet climate-specific building codes. Accurate calculations prevent underinsulation (poor efficiency) or overinsulation (wasted money).
Related calculators
Roof Shingle Calculator
Estimate the number of shingle squares and bundles required for any roof area and pitch.
Paint Calculator
Find out how many litres of paint you need to cover any room or surface.
Energy Converter
Convert joules, calories, kWh, BTU, and electronvolts for science, cooking, and engineering.
Learn more
The complete guide to insulation calculator
Formulas, examples, and tips explained in plain English