RSI (m²·K/W) (m²·K/W)
The square metre kelvin per watt (RSI) is the SI unit of thermal resistance of a building element: R = d/λ for each layer, and the U-value is 1/ΣR. ECBC and the EU specify wall and roof insulation in m²·K/W.
Symbol: m²·K/W (ASCII: m2 K/W)
Quantity: thermal resistance per unit area (insulation R-value)
SI relation: m²·K/W is the coherent SI unit of thermal resistance (r-value).
Derivation: Thermal resistance per unit area R = thickness ÷ conductivity, in m²·K/W; U = 1/ΣR.
Exact: yes, by definition
Typical uses
- Building envelope design (ECBC, Part L, EN ISO 6946)
- U-value calculations
- Insulation product labels outside the US
Convert square metre kelvin per watt to other units
| Conversion | 1 m²·K/W equals | Reverse |
|---|---|---|
| RSI to R (US) | 5.678263341 ft²·°F·h/BTU | R (US) to RSI |
| RSI to clo | 6.451612903 clo | clo to RSI |
| RSI to tog | 10 tog | tog to RSI |
| RSI to square metre hour degree Celsius per kilocalorie | 1.163 m²·h·°C/kcal | square metre hour degree Celsius per kilocalorie to RSI |
Open the R-Value Converter (US R to RSI, m²·K/W) to convert any value between all units.
Sources
- The International System of Units (SI), 9th edition (SI Brochure), Bureau International des Poids et Mesures , Table 4 (derived units with special names).
Last reviewed: . Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.
Cite this page
APA
Scientific Converters. (2026, October 15). RSI (m²·K/W) (m²·K/W). Retrieved October 29, 2026, from https://scientificconverters.com/units/square-meter-kelvin-per-watt/
IEEE
Scientific Converters, "RSI (m²·K/W) (m²·K/W)," scientificconverters.com. Accessed: Oct. 29, 2026. [Online]. Available: https://scientificconverters.com/units/square-meter-kelvin-per-watt/