Coming into popular use during the 19th century, cast iron radiators provided a much more consistent heat with less expense than burning multiple fires in a dwelling. Installing a central heating system that required only one fire to keep in operation cut coal and consumption drastically.
By retrofitting an existing dwelling to a steam oriented central system, it was possible to install a natural gas heater for even greater energy cost savings over coal or wood fuel.
Cast iron radiators are made sectionally so that heat could be evenly distributed throughout the system. A smaller room would require fewer "columns" in the radiator than would a larger room. With fashion in mind, the cast iron radiator columns were made at different heights. A column radiator offers practical heating solutions. Planning a room's decor could combine different heights for aesthetic appeal as well as practical application.
It required figuring the dimensions of a room to determine the size for the radiator for each room. Having too great an amount of radiating surface for the area would severely overheat the room, while too little would prevent the system from working effectively there.
Since cold air drops, cast iron radiators need to be placed in the potentially coldest part of a room. This way the air is heated as it crosses the radiator fins and will create less temperature inversion. Areas where cast iron radiators are most effective are around windows and at the bottom of stairwells.
Unlike contemporary steel constructed radiators which cause quicker heat transfer, the old fashioned cast iron radiator will provide a more consistent warmth by transferring the heat into the atmosphere around the radiator more slowly. An added benefit to this slower heat exchange is that it greatly reduces the amount of condensation and damp that has such a detrimental effect on the physical integrity of the system.