Convert International table BTU per hour per square foot to Milliwatt per square metre
Convert International table BTU per hour per square foot (BTU(IT)/(h·ft²)) to Milliwatt per square metre (mW/m²) instantly and accurately.
Conversion Formula
mW/m² = BTU(IT)/(h·ft²) × 3154.590745
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 Milliwatt per square metre
The milliwatt per square metre (mW/m²) equals 10⁻³ W/m². Relevant in geothermal surveys: global average continental heat flux ≈ 65 mW/m², oceanic ≈ 101 mW/m². Used in building physics for quantifying very small heat leakage through ultra-high-performance insulation. 1 mW/m² = 10⁻³ W/m² = 1 erg/(s·cm²).
Quick Reference Table
| International table BTU per hour per square foot (BTU(IT)/(h·ft²)) | Milliwatt per square metre (mW/m²) |
|---|---|
| 1 BTU(IT)/(h·ft²) | 3154.59 mW/m² |
| 2 BTU(IT)/(h·ft²) | 6309.18 mW/m² |
| 5 BTU(IT)/(h·ft²) | 15773 mW/m² |
| 10 BTU(IT)/(h·ft²) | 31545.9 mW/m² |
| 25 BTU(IT)/(h·ft²) | 78864.8 mW/m² |
| 50 BTU(IT)/(h·ft²) | 157730 mW/m² |
| 100 BTU(IT)/(h·ft²) | 315459 mW/m² |