As of 2015, boilers offer the most cost-effective heating for most homes. People in warmer regions or small homes, however, may find the upfront cost to be too high.
Fireplaces vent most of their generated heat through the chimney, making them expensive and inefficient. Electrical heating systems are expensive to operate and are mostly used in regions where they are rarely needed.
Furnaces offer better efficiency than fireplaces and may be a reasonable investment for heating a single room or mobile home. The cost of blowing air throughout an entire building, however, leads to poor efficiency. Boiler systems, particularly hot water systems, provide the best fuel efficiency for most building sizes.