Construction
Insulation Calculator: R-Value
Calculate insulation R-value and materials.
Proper insulation saves energy.
R-Value
Resistance to heat flow. Higher = better.
Recommended
- Attic: R-38 to R-60
- Walls: R-13 to R-21
- Floors: R-25 to R-30
Types
- Fiberglass: R-3.1-3.4/inch
- Spray foam: R-6-7/inch
- Cellulose: R-3.2-3.8/inch
Frequently Asked Questions
Wall R-value?
R-13 to R-21 depending on climate.
R-value meaning?
Heat flow resistance. Higher = better.
Best type?
Spray foam highest R/inch. Batts DIY-friendly.