Convert International table BTU per hour per square foot to Thermochemical kilocalorie per hour per square metre
Convert International table BTU per hour per square foot (BTU(IT)/(h·ft²)) to Thermochemical kilocalorie per hour per square metre (kcal(th)/(h·m²)) instantly and accurately.
Conversion Formula
kcal(th)/(h·m²) = BTU(IT)/(h·ft²) × 2.71427502
About International table BTU per hour per square foot
The international table BTU per hour per square foot (BTU(IT)/(h·ft²)) equals 1055.05585262/(3600×0.09290304) ≈ 3.15459 W/m². The standard US heat flux unit in ASHRAE, ASTM, and building codes for thermal resistance (R-value), boiler ratings, and heat exchanger design. 1 BTU(IT)/(h·ft²) ≈ 3.15459 W/m².
About Thermochemical kilocalorie per hour per square metre
The thermochemical kilocalorie per hour per square metre (kcal(th)/(h·m²)) equals 4184/3600 ≈ 1.1622 W/m² (1 kcal(th) = 4184 J; 1 h = 3600 s). Used in older continental European and Soviet-era building physics standards for wall and roof heat loss calculations. 1 kcal(th)/(h·m²) ≈ 1.1622 W/m².
Quick Reference Table
| International table BTU per hour per square foot (BTU(IT)/(h·ft²)) | Thermochemical kilocalorie per hour per square metre (kcal(th)/(h·m²)) |
|---|---|
| 1 BTU(IT)/(h·ft²) | 2.71428 kcal(th)/(h·m²) |
| 2 BTU(IT)/(h·ft²) | 5.42855 kcal(th)/(h·m²) |
| 5 BTU(IT)/(h·ft²) | 13.5714 kcal(th)/(h·m²) |
| 10 BTU(IT)/(h·ft²) | 27.1428 kcal(th)/(h·m²) |
| 25 BTU(IT)/(h·ft²) | 67.8569 kcal(th)/(h·m²) |
| 50 BTU(IT)/(h·ft²) | 135.714 kcal(th)/(h·m²) |
| 100 BTU(IT)/(h·ft²) | 271.428 kcal(th)/(h·m²) |