Thermal Conductivity Converter
Convert thermal conductivity (k-value, λ) between W/(m·K), BTU/(h·ft·°F), BTU·in/(h·ft²·°F), cal/(s·cm·°C) and other units.
1 watt per meter kelvin = 0.5777893165 BTUs per hour foot degree Fahrenheit
Most used thermal conductivity units
- Watt per meter kelvin W/(m⋅K) Base unit
- BTU per hour foot degree Fahrenheit BTU/(h⋅ft⋅°F) 1 BTU/(h⋅ft⋅°F) = 1.7307347 W/(m⋅K)
- BTU inch per hour square foot degree Fahrenheit BTU⋅in/(h⋅ft²⋅°F) 1 BTU⋅in/(h⋅ft²⋅°F) = 0.14422789 W/(m⋅K)
- Milliwatt per meter kelvin mW/(m⋅K) 1 mW/(m⋅K) = 0.001 W/(m⋅K)
- Calorie per second centimeter degree Celsius cal/(s⋅cm⋅°C) 1 cal/(s⋅cm⋅°C) = 418.4 W/(m⋅K)
- Kilocalorie per hour meter degree Celsius kcal/(h⋅m⋅°C) 1 kcal/(h⋅m⋅°C) = 1.163 W/(m⋅K)
- Watt per centimeter kelvin W/(cm⋅K) 1 W/(cm⋅K) = 100 W/(m⋅K)
Popular thermal conductivity conversions
- Watts per meter kelvin to BTUs per hour foot degree Fahrenheit 1 W/(m⋅K) = 0.5777893 BTU/(h⋅ft⋅°F)
- BTUs per hour foot degree Fahrenheit to watts per meter kelvin 1 BTU/(h⋅ft⋅°F) = 1.730735 W/(m⋅K)
- BTU inches per hour square foot degree Fahrenheit to watts per meter kelvin 1 BTU⋅in/(h⋅ft²⋅°F) = 0.1442279 W/(m⋅K)
- Watts per meter kelvin to BTU inches per hour square foot degree Fahrenheit 1 W/(m⋅K) = 6.933472 BTU⋅in/(h⋅ft²⋅°F)
What is thermal conductivity?
Thermal conductivity (k or λ) describes how easily heat flows through a material. Metals conduct heat well (copper about 400 W/(m·K)), while insulation materials conduct it poorly (mineral wool about 0.035 W/(m·K)). The SI unit is the watt per meter-kelvin. In US building work the "k-value" is usually given in BTU·in/(h·ft²·°F).
Dividing a layer's thickness by its thermal conductivity gives its thermal resistance, the R-value.
Thermal conductivity units from smallest to largest
Every proportional thermal conductivity unit on the site, ordered by size and expressed in watts per meter kelvin.
- Milliwatt per meter kelvin 0.001 W/(m⋅K)
- BTU inch per hour square foot degree Fahrenheit 0.144228 W/(m⋅K)
- Watt per meter kelvin 1 W/(m⋅K)
- Kilocalorie per hour meter degree Celsius 1.163 W/(m⋅K)
- BTU per hour foot degree Fahrenheit 1.73073 W/(m⋅K)
- Watt per centimeter kelvin 100 W/(m⋅K)
- Calorie per second centimeter degree Celsius 418.4 W/(m⋅K)
All 7 thermal conductivity units
Units
Frequently asked questions
What is a good thermal conductivity for insulation?
Below about 0.04 W/(m·K). Mineral wool and fiberglass are 0.032–0.040, EPS about 0.035, polyurethane foam about 0.022–0.028.