The Initial Costs of Gas Vs. Electric Furnaces

Gas Furnace Cost

• Replacing an older, low-efficiency gas furnace can run from $1,700 to $6,000 as of August 2011. The wide range of prices is because gas furnaces come in a broader range of heating capacity and efficiency ratings. The heating capacity is based on the furnace's British Thermal Unit (BTU) output. The bigger your house and the higher your ceilings -- the more BTU capacity you will need. A $1,700 furnace might take care of a 1,200-square-foot home, but it wouldn't nearly accommodate the heating needs of a two-story home with 2,000 square feet of space. The other factor is the furnace's Annual Fuel Utilization Efficiency rating. A new, energy-efficient gas furnace with a 95 AFUE might be exactly what you need if you live in Wisconsin and have a two-story home. In that case, you should prepare to spend at least $4,000 on a new energy-efficient gas furnace.

Gas: Additional Initial Costs

• Just as it is with an electric furnace, the big-ticket potential addition to your budget could be if ductwork is required. For example, if you are replacing an old pipe system with a duct system to make the switch to central heating, the ductwork could run from several hundred to over $1,000 as of August 2011. In terms of installation, you should expect installation to range anywhere from $1,000 to $2,000 for a gas furnace --- depending on whether ductwork is involved.

Electric Furnace

• Electric furnaces can range from around $600 to $1,500 as of August 2011. Prices are based on the CFM (cubic feet per minute) of heated (or cooled) air that the furnace is capable of delivering. For example, an 800 CFM electric furnace will warm 800 cubic feet of air per minute, and a 2,000 CFM furnace (one of the largest options for residences) will heat 2,000 cubic feet per minute. The lower the CFM, the smaller the unit, and the lower the cost. An 800 CFM might cost $600, while a 2,000 CFM might cost $1,500. The 800 CFM furnace will accommodate a one-story home with 2 or 3 bedrooms, while a 2,000-square-foot home with 4 bedrooms and attic space will more than likely require a 2,000 CFM electric furnace.

Electric Furnace: Additional Initial Costs

• Don't get ready to write a check for $600 or $1,500 just yet. Those amounts will just get you far enough for the salesperson to put a sticker that says "sold" on the electric furnace you select. As is the case with a gas furnace, you will need the right ductwork system to create a forced-air heating and cooling setup, and the cost can easily run over $1,000, based on the complexity of the job and the size and number of stories of your home. You may also need to factor in electrical work, such as converting outlets to 220-volt capacity. Finally, factor in installation costs, which could easily run anywhere from $1,700 to $3,500. All prices are as of August 2011.