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BTU Calculator

Our shiny, brand new BTU calculator will help you work out which radiator will most effectively heat your room. BTU stands for British Thermal Units and it represents the level of heat a radiator provides.

This figure is calculated by taking into account the dimensions of your room (width, length, height) and the type of windows (such as single or double glazing). You can either use one radiator to reach the total BTU level required, or a number of radiators which reaches the required BTU level when added together - let’s get to it!

Step 1

Step 2

What are the dimensions of your room?

Step 3

Which type of windows & doors do you have?

Every radiator is given a BTU rating which we have highlighted on each product page on

The required BTU level to heat your room will influence the size of your radiators, but do not fear, we have numerous options for you to choose from. It definitely helps to consider the space that you have before making a final decision.