Save time, money, and hassle with our radiator calculator and BTU calculator tools. We have created both to make it easy to find exactly the right radiators for your next installation.
Use our free BTU calculator to understand the heating requirements of a room. Our simple, five step tool goes through everything you need to calculate heat loss, so you know exactly the BTU needed to warm a room comfortably.
For answers to common questions around BTU calculations, head to our BTU FAQ section.
Our radiator calculator and selector tool combines everything you need to work out exactly what is required to warm a room. It allows you to use your BTU requirements and the room’s specifications to find exactly the right product from our extensive range of central heating radiators and heated towel rails. This makes it quick and painless to find what you ned to get the job done.
For detailed instructions on how to use the radiator selector, read our how to guide or download as a pdf:
Select the room, enter the BTU requirement if known, if not known, use the Heat Loss Calculator.
Select your requirements – room type, room size, radiator type, radiator size etc.
View the products and details of your selection.
Simply add the products to your basket, and then proceed to the checkout to order for collection or delivery.
Here we answer some of the commonly asked questions around BTU calculations.
BTU stands for British Thermal Unit. The precise definition is that a BTU is the amount of heat energy needed to warm one pound of water by one degree Fahrenheit. This means that BTUs are an imperial measurement.
BTUs are the industry standard measurement of heat output for radiators – the larger the BTU value the more heat a radiator can provide.
The short answer is that 3412 BTU = 1kW.
If you want to be technically correct, BTU is a measure of energy whereas kWs are a measure of power. So, it is more accurate to say that 1kW is equivalent to 3412 BTU/h (BTU per hour).
To do a thorough calculation of the BTUs needed to heat a room, there are five things to consider:
Our easy-to-use BTU calculator runs through each of these step-by-step to ensure you get the most accurate results.