To the calculate heat requirement for your room a good rule of thumb is:
Height x Width x Depth (in feet) divided by 500. This gives you the kilowatt requirement. This is based on the average house insulation with a room temperature of 20 degrees and an ambient temperature of -1C. Well-insulated houses can replace the division of 500 with 650.
To get the BTUs requirement multiply the kilowatt requirement by 3,400.
- To convert BTU to Kw simply multiply by 0.000293
- To convert Kw to BTU simply multiply by 3414