BTU per hour-foot-Fahrenheit
Thermal conductivityexact by definition
The BTU per hour per foot per Fahrenheit degree is the customary US unit of thermal conductivity, equal to 1.730735 W/(m·K). The relation is exact by definition, following from the International Table BTU, the international foot of exactly 0.3048 m, the hour and the Fahrenheit degree of 5/9 K, though the decimal shown is a rounding of that exact ratio.
Watch out: US insulation literature more often quotes conductivity per INCH of thickness, in BTU·in/(h·ft²·°F), which is twelve times this unit. That per-inch form is the reciprocal of R-value per inch: fibreglass at R-3.2 per inch has a conductivity of 1/3.2 = 0.31 BTU·in/(h·ft²·°F), which is 0.026 in this unit and 0.045 W/(m·K). Check the exponent on the foot before converting.
| 1 | 1.7307347 |
One btu per hour-foot-fahrenheit in every thermal conductivity unit
| 1,730.73 | milliwatt per meter-kelvin (mW/(m·K)) | |
| 12 | BTU inch per hour square foot Fahrenheit (BTU·in/(h·ft²·°F)) | |
| 1.73073 | watt per meter-kelvin (W/(m·K)) | convert → |
| 1.73073 | watt per meter-Celsius (W/(m·°C)) | |
| 1.48916 | kilocalorie per hour meter Celsius (kcal/(h·m·°C)) | |
| 1 | BTU per hour-foot-Fahrenheit (BTU/(h·ft·°F))this unit | |
| 0.0173073 | watt per centimeter-kelvin (W/(cm·K)) | |
| 0.00413656 | calorie per second centimeter Celsius (cal/(s·cm·°C)) | |
| 0.00173073 | kilowatt per meter-kelvin (kW/(m·K)) |