Struggling to work out your BTU's or heat output requirement? Use our quick and easy calculator below to find out your specific room requirements.

Calculate you require heat output

Enter your room details below, to find out their required heat output

Please note, this is a guide only. A radiator with insufficient output may never raise the temperature to that required. Outdoor temperatures, external walls, insulation, heated adjacent rooms (i.e. above, below and to the side) all play a part.

The boiler should be sufficient to supply all connected radiators to the sum of their maximum demand.

Larger rooms such as Living Rooms may require more than one radiator positioned evenly throughout the room. If this is the case, divide the required output between the number of radiators needed.

Step 1 Enter Room information
Step 2 Enter Room Dimensions

Please select whether like to provide the room dimensions in meters or feet

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