4 units · base unit m²·K/W · M⁻¹ T³ Θ

R-value & insulance converter

US R-values and metric RSI values differ by a factor of 5.678, so an "R-30" batt is RSI 5.28. Quoting the wrong one overstates insulation almost sixfold.

5.678 263 341 11ft²·°F·h/BTU
≈ Rounded to 12 s.f. 1 m²·K/W ≈ 5.678 263 341 11 ft²·°F·h/BTU
As a fraction: 52752792631/9290304000
1 m²·K/W = 5.67826334111 ft²·°F·h/BTU

Common r-value & insulance conversions

All r-value & insulance units

Each unit expressed in rsi (m²·k/w)s (m²·K/W), the unit everything in this category converts through.

Unit Symbol System Value in m²·K/W
RSI (m²·K/W) m²·K/W SI 1
R-value (US) ft²·°F·h/BTU imperial 0.176110183682
Clo clo other 0.155
Tog tog other 0.1

About r-value & insulance units

Convert R-value (US), RSI, clo and tog insulation ratings.

US R-values and metric RSI values differ by a factor of 5.678, so an "R-30" batt is RSI 5.28. Quoting the wrong one overstates insulation almost sixfold.

Dimensional formula: M⁻¹ T³ Θ. Every conversion on this page goes through the rsi (m²·k/w), using exact fractions rather than decimal approximations. Read how that works →