A: At Foundry, we recommend using a BTU heat loss calculator to accurately determine the heating requirements of your room before selecting a radiator. This calculator considers factors such as room size, insulation, window type, and external wall exposure to estimate the total British Thermal Units (BTU) needed to maintain a comfortable temperature. Once you know the required BTU output, you can choose from our range of cast iron, steel, or aluminium radiators that match or slightly exceed this figure, ensuring efficient and consistent heating. Our luxury cast iron radiators are particularly effective due to their high thermal mass, providing sustained warmth and complementing classic or contemporary interiors. If you need assistance interpreting your heat loss results or selecting the perfect radiator, Foundry Cast Iron's experts are available to guide you through the process for optimal comfort and energy efficiency.