How to choose the right radiator

A radiator that's too small doesn't heat, one that's too big wastes. The right choice depends on the room size, how many walls face outside and the type of system you have. That's why a calculation matters, not the eye.

As for material, steel is a good price-to-heat ratio, aluminum heats up fast, and cast iron holds heat for a long time. I'll tell you on site what suits your room. See also radiator fitting.