BTU Calculator

Sizing a radiator for a room is not as easy as just putting in what was already there, radiators are now more efficient than they were in past years.

As such, rooms need to be re-calculated so that you are not over heating a room with a radiator of too much output and therefore using more energy than is required; or under heating a room with a radiator with insufficient output, may never raise the temperature to that required!

Using the calculator below, you will be able to accurately size your radiators and then find the ideal size for you room. This calculator is for a guide only!

Room Details

Fill in the details of the room you wish to add, then click the 'Add Room' button. A summary of the rooms you have added can be found in the section below.

Name of Room : Type of Room : Bathroom Living Room Bedroom Hallway or Kitchen What is below the Room? : Heated Room Wooden Floor Solid concrete Floor Suspended Concrete Floor What is above the Room? : Heated Room A Pitched Roof Pitched Roof Insulated 50mm Pitched Roof Insulated 100mm Flat Roof Flat Roof Insulated Type of Outside Walls : Brick Cavity Insulated Brick Cavity 105mm Solid Brick 220mm Solid Brick Wood frame Type of Windows : None Wood/Plastic Double Glazed Metal Double Glazed Metal Single Glazed Wood Single Glazed Number of Outside Walls : None One Two Three Height of Room (m) : Width of Room (m) : Length of Room (m) : Window Area (m²) : BTU's Required: Watts Required:

House Summary

Below you will see the outputs of the radiators you require in BTU (British Thermal Units).