Convert btu (it)/hour/square foot to watt/square metre

Please provide a value.
Please provide a value.

Btu (IT)/Hour/Square Foot

The British thermal unit (IT) per hour per square foot (Btu/(h·ft²)) equals approximately 3.155 W/m² and is the most common imperial unit of heat flux in North American HVAC and building engineering. It is used for heat loss calculations, U-values, and thermal performance ratings of building envelopes. 


Watt/Square Metre

The watt per square metre (W/m²) is the SI unit of heat flux density and irradiance. It represents the power transmitted per unit area. The solar constant (total solar irradiance) at Earth's orbit is approximately 1361 W/m². Used in heat transfer engineering, solar energy, and thermal radiation analysis. 


Btu (IT)/Hour/Square Foot to Watt/Square Metre conversion table
Btu (IT)/Hour/Square FootWatt/Square MetreWatt/Square MetreBtu (IT)/Hour/Square Foot
13.1545910.316998
26.3091820.633997
39.4637730.950995
515.77351.58499
1031.5459103.16998
2063.0918206.33997
2578.8648257.92496
50157.735015.8499
100315.45910031.6998
250788.64825079.2496
5001577.3500158.499
10003154.591000316.998
How to convert Btu (IT)/Hour/Square Foot to Watt/Square Metre

1 Btu/(h·ft²) = 3.15459 W/m². To convert any value, multiply it by 3.15459. For example, 25 Btu/(h·ft²) = 78.8648 W/m².

Frequently asked questions
How many W/m² are there in one Btu/(h·ft²)?
One Btu/(h·ft²) is equal to 3.15459 W/m².
How do you convert Btu (IT)/Hour/Square Foot to Watt/Square Metre?
Multiply the value in Btu (IT)/Hour/Square Foot by 3.15459 to get the result in Watt/Square Metre.
How much is 25 Btu/(h·ft²) in W/m²?
25 Btu/(h·ft²) is equal to 78.8648 W/m².
How do you convert Watt/Square Metre back to Btu (IT)/Hour/Square Foot?
Divide by the same factor: multiply the value in Watt/Square Metre by 0.316998 to get Btu (IT)/Hour/Square Foot.

Most common heat flux density unit conversions