Insulation Calculator
Calculate R-value, thermal resistance, and insulation requirements for energy efficiency
Calculate Insulation R-Value
Insulation Layers
Layer 1
Layer 2
Insulation Performance
💡 Energy Efficiency Tips
• Higher R-values provide better thermal resistance and energy savings
• Consider air sealing to prevent thermal bridging and air leakage
• Continuous insulation reduces thermal bridges through framing
• Vapor barriers may be required in certain climate zones
• Professional installation ensures optimal performance
Example Calculation: Insulated Wall System
Wall Assembly
Layer 1: 0.5" Gypsum Board (Drywall) - R-0.45
Layer 2: 3.5" Fiberglass Batt Insulation - R-11.9
Layer 3: 0.75" Plywood Sheathing - R-0.94
Layer 4: 1" XPS Foam Board - R-5.0
Total Thickness: 5.75 inches
Thermal Performance
• Total R-Value = 0.45 + 11.9 + 0.94 + 5.0 = R-18.29
• U-Value = 1 ÷ 18.29 = 0.055 BTU/hr·ft²·°F
• Excellent thermal performance for cold climates
Result: High-performance wall assembly
R-Value Recommendations
Walls
Attics
Floors
Insulation Types
Batt/Blanket
Pre-cut panels, easy installation, good for standard framing
Loose Fill
Blown-in material, good for irregular spaces and retrofits
Foam
High R-value, air sealing properties, continuous coverage
Rigid Boards
Structural strength, continuous insulation applications
Quick Reference
Understanding Insulation and R-Values
What is Insulation?
Insulation is material that resists heat flow through conduction, convection, and radiation. It creates a thermal barrier that helps maintain indoor temperatures, reducing energy consumption for heating and cooling.
R-Value Basics
- •R-Value measures thermal resistance per unit thickness
- •Higher R-values indicate better insulating properties
- •Total R-value is the sum of all layer R-values
- •Thicker insulation increases total R-value
Calculation Formula
Total R-Value = R₁ × t₁ + R₂ × t₂ + R₃ × t₃ + ...
- R₁, R₂, R₃: R-value per inch of each material
- t₁, t₂, t₃: Thickness of each layer (inches)
- U-Value: 1 ÷ Total R-Value (thermal transmittance)
Critical Considerations
Installation Quality
Proper installation is crucial - gaps and compression reduce effectiveness.
Air Sealing
Air leaks can significantly reduce insulation performance.
Climate Zone
Local climate determines appropriate R-value requirements.