Convert insulation R-value, RSI value, U-factor, U-value, and thermal resistance units for construction, insulation, walls, roofs, floors, and building envelope estimates.
R-value to RSI:
RSI = R × 0.17611
RSI to R-value:
R = RSI × 5.67826
R-value to U-factor:
U = 1 ÷ R
RSI to U-value:
U = 1 ÷ RSI
Insulation R-value conversions are useful for walls, attics, roofs, floors, basements, crawl spaces, garage insulation, windows, doors, and building envelope planning.
Use this converter when comparing US R-values, metric RSI values, U-factors, U-values, insulation specs, and energy-related construction measurements.
Your result shows the entered insulation value converted from the starting unit into the selected ending unit. R-value and RSI measure resistance to heat flow. U-factor and U-value measure heat transfer.
A higher R-value or RSI generally means better insulation resistance. A lower U-factor or U-value generally means less heat transfer through the material or assembly.
R-value measures how well a material resists heat flow. Higher R-values usually mean better insulation resistance.
RSI is the metric version of R-value. It is measured in square meters kelvin per watt.
Multiply the US R-value by 0.17611. For example, R-13 is about RSI 2.29.
Multiply RSI by 5.67826. For example, RSI 3.5 is about R-19.87.
R-value measures resistance to heat flow. U-factor measures heat transfer. They are inverses of each other within the same unit system.