Could anyone help me with this question please? I want to fit a radiator on my landing. The measurements are roughly 2.5m x 2.5m x2.5m. I have looked at some BTU calculators but they seem to be specifically for rooms.Can anyone suggest the size of radiator I should go for taking into account the loft above is uninsulated and there will be a certain amount of heat loss back down the stairs. There is also a single glazed window 1.5m x0.25m. Thanks