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Radiator BTU Calculator

When you're installing a new heating system, or replacing your old one, it's important that you choose the right radiator for the space you want to heat. Heat output is measured in BTU (British Thermal Unit) and is the best way to work out how much radiator power you need. For more information on what affects BTU, please click here

Use our calculator below to work out the number of BTU you need for your space. All of our radiators list the BTU levels so you can easily find the right one for you.

Radiator BTU Calculator

Where is the radiator to be placed?
What factors do you want to consider?
Feet x
Feet x

There are several factors that can affect the amount of BTU that you need. You should first take into account elevation. Floors on upper levels will receive heat from the sun and therefore will need less heating power. You should also take into account the insulation in your property and the direction of sunlight. For example, rooms at the front and back of the house may get direct sunlight through the windows during the day, requiring less heating.

Another important factor is windows. If you have single glaze windows, chances are you’ll need more heating. Vice versa, if you have double gazed or triple glazed windows, you’ll need slightly less. You should also consider the moisture levels in the room you’re looking to install in. Kitchens and bathrooms, for example, have a higher moisture level than other rooms. These rooms will need less heating than others, as appliances such as stoves and showers give off warmth.

We stock a huge range of radiators with a variety of BTU’s. With well-known brands such as Honeywell, Stelrad, Steibel, and more, you are guaranteed to find the ideal heating solution for your property.