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Ideas & Advice

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Radiator BTU calculator

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Radiator BTU calculator

The heat output or 'BTU' (British Thermal Unit) calculator is a great way to work out how much radiator power you need. There are several factors which can affect this, such as room dimensions, heating levels and types of window, which are all covered in our radiator BTU calculator. Please note: You may need several radiators for bigger rooms.

How do I choose the right radiator?

The BTU value of all our radiators is clearly labelled in-store and online, helping you find those which suit your requirements.

Which room you are heating?
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What are the dimensions of the rooms?




What type of windows or doors are in the room?

Your BTU result