Construction & Materials
R-Value to U-Factor Calculator
Convert insulation R-value to U-factor (thermal transmittance), and vice versa.
Your inputs
Change any value to update the result instantly.
U-factor
0.0526 BTU/(ft²·°F·hr)
R-value
19 ft²·°F·hr/BTU
Metric U-value
0.299 W/(m²·K)
Formula and working
U = 1 ÷ R
- 1
Collect the inputs
Total R-value = 19 ft²·°F·hr/BTU
- 2
Apply the formula
U = 1 ÷ R
- 3
Result
U-factor = 0.0526 BTU/(ft²·°F·hr)
Frequently asked questions
Important limitation
This is an educational estimate based only on the values and formula shown. Verify current rates, rules, units, and professional standards before relying on the result. It is not personalized financial or investment advice.
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