Variable weather and high winds make difficult the economical use of fuel and convenient operation.

Size And Type Of Dwelling

Fuel consumption varies with the size of the house, the number of rooms heated, the thoroughness of construction, to a certain extent the building material, and the distribution of the radiators.

Location Of Dwelling

A house standing alone on a hill requires much more heat than one in a closely built row standing in a hollow.

Heating And Ventilating System Used

Convenience of operation of any house-heating apparatus is largely dependent on the system of heating and ventilation employed. The cost of heating will also depend, but to a less degree, on the type of equipment. Fuel economy and convenience are against a separate fire in each room unless the house is small or only a small part of it is to be warmed, except in those localities where natural gas is available at low rates or the duration of cold weather is brief. In comparatively few homes is any special provision made for removing the foul air, leakage from windows and doors being the usual reliance, particularly in a house heated by a hot-air furnace. If an indirect steam or hotwater system is installed, means of removing foul air are more frequently provided, either by vent stacks leading into the attic or through the roof, with register openings in different rooms, or by open grates, the flues for which can be equipped with dampers to regulate the removal of foul air. The system sometimes fails to work satisfactorily if provision is not made for the escape of foul air from a room, as the fresh warm air will not continue to flow in unless an equal amount escapes. The first cost of heating by the hot-air furnace is less than that of either the steam or the hot-water system, but to maintain equal temperature conditions may require the burning of more fuel, whether the furnace heats air taken from outdoors or reheats air already in the house. Evidently, reheating air will require less fuel, and consequently less attention to the furnace, than heating fresh air, but the ventilation will not be good. In homes heated by steam or hot water, the method of heating, whether direct or indirect, and the provision, if any, for removing foul air will affect the consumption of fuel, which will vary with the percentage of the total radiation that is indirect and with the amount of warm air removed through vent stacks or grates. . A furnace-heating system maintains a less even temperature because less heat is stored in it. In this respect, hot-water heating has a distinct advantage over both steam and hot air because the large quantity of water in the boiler, pipes, and radiators can maintain the temperature throughout the house for a considerable time after the fire dies down. In addition, the maintenance of an even temperature in mild weather is easier with the hot-water system because the temperature of the water in the radiators, hence the amount of heat given off, can be controlled within wide limits.

* Condensed from Saving Fuel in Heating a House. L. P. Breckenridge and S. B. Flagg. Bur. of Mines, U. S. Dept. of the Interior, Tech. Paper 97.