Save time, money and hassle with our online radiator calculator and BTU calculator

Designed to help you decide the specific radiator size and power required to meet your needs, our innovative BTU radiator calculator tool makes finding the perfect radiator simple.

Within the tool you’ll find our Heat Loss & BTU Calculator, which helps you calculate the BTU (British Thermal Unit) that you require to effectively heat your room. Using this calculator, as well as providing information about which style of radiator you desire and the space you have available, you can instantly find radiators that will suit your needs.

Discover superior radiators in our Radiator Selector tool at Wolseley and make the most of our competitive trade prices, fast home delivery, and free in-branch collection.

How to guide


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.