Radiator Calculator

Estimate your room's BTU/watts requirement below:

  • Room Information

  • Room Dimensions

  • Metres Feet
  • m
Please enter valid room dimensions and choose your room type to see result

The calculator results shown above should only be used for guidance and are not guaranteed to be correct for your requirements as every project is unique.

Our radiator calculator uses information about your room to estimate the requirements of heating the room in BTU (British Thermal Units of heat energy) and watts (a standard unit of the heat power required to be generated out of a radiator to heat your room). Bear in mind the result of the radiator calculator will show the minimum required to heat the room, not the maximum, so you will want to install radiators that provide more watts and BTU than the calculator. Remember this is a guide rather than an exact science.

Radiator BTU Calculator

After using our radiator calculator, you can use the results to figure out how many radiators you will need. On each of our radiator product pages, in the product details section, you will see a "heat output per section" value such as 160 watts/547 BTU. If the radiator btu calculator recommends you need  2255 BTU and 661 watts, you divide that by the watt and BTU per section values of the radiator you want, and that's how many sections of that length you would need. In this example you would need 4.13 sections, rounded up to 5 sections.

Browse the radiators we have in stock below or give us a call on (01889) 574 066 if you have any questions.

Cast Iron Radiators, Valves and Accessories

This is the privacy policy sample page.
It was created automatically and do not substitute the one you need to create and provide to your store visitors.
Please, replace this text with the correct privacy policy by visiting the Customers > GDPR > Privacy Policy section in the backend.