BTU Calculator

A British Thermal Unit (BTU) is a measure of heat output from a radiator. Depending on the size of your room, the number and type of windows and what the room is used for, you'll need more or less heat. If you have a higher BTU requirement, it might be better to use more than one radiator to deliver the heat you'll need to a room. The total BTU output of several smaller radiators may meet your needs.



  Length Width Height



Room Type?


Does the room have?

  French Windows  
    North Facing Walls  
    Double Glazing  
  Required BTU Watts

This calculator will give an approximate value of the BTU requirement for your room. Consider other factors such as if the room has large windows or more than one outside walls.


Please call us on 01663 749027 for advice.