gas fireplace 

Alternatives to Conventional Woodburning Fireplaces

Pellet Stoves


  • Indoor and outdoor emissions are reduced - among the cleanest burning of all the new technologies.
  • Greater heat output and energy efficiency.
  • Easy to use and ideal for those who don’t like to chop or haul wood. Longer periods between refueling.
  • Can burn on Air Quality Action Days.
  • Heat output can be set manually or automatically controlled by a thermostat.
  • Controls air-to-fuel ratios and feed rates to ensure everything is burned.
  • Pellets made from waste wood (compressed sawdust, waste wood, paper, peanut shells, or corn) have less moisture content than regular wood, therefore use less energy to burn and increase heat output.

It is important to follow the manufacturer’s recommendations because using the incorrect pellet may form lava-like deposits called “clinkers” making your stove less effective.


  • Cost ranges $2500 to $4000.
  • Cost of pellets is approximately $250/ton (50 bags).
  • Limited availability of pellets in some areas which can increase cost.
  • The motor and fan is dependant on power and will not work during a power failure.

Certified Wood Stoves

(freestanding and inserts)


  • Greatly reduces particulate and carbon monoxide emissions (particulate pollution by 90% & carbon monoxide emissions by 60%)
  • Generates little or no creosote buildup
  • Newer wood stoves emit five times less pollution than older models, and produce 50% more heat. There are two categories of certified wood stoves: catalytic and non-catalytic.

Catalytic burners contain a special device that works similarly to that of the catalytic converter in a car. The converter reduces ignition temperature from 1100°F to 550°F, enabling more complete combustion. A lower temperature means more fuel and smoke are ignited before emissions exit the flue.

Wood stoves with catalytic converters generally have better heating efficiency and longer burn periods; however, the burner needs to be replaced every three to six years. Wood stoves with catalytic burners range from $1000 to $3000. 


Disadvantages are the maintenance of the catalytic device.

Non-catalytic wood stoves use a series of pipes to bring additional air into the firebox, creating a secondary burn which combusts smoke before it exits the flue. Although easier to maintain, they do produce more emissions and burn more wood than catalytic stoves. Non-catalytic woodburning stoves cost between $1000 and $5000.

To ensure that you are purchasing an EPA Phase II/Colorado Phase III certified stove, look for the certification label and a stove manufactured after July 1, 1991. Stoves manufactured prior to this date do not meet the standards for carbon monoxide and particulate emissions.

Natural Gas Fireplaces


  • Reduces emissions
  • Convenient (instant on/off) control
  • No wood required
  • Safe (no sparks or creosote buildup)
  • Costs less than other fuels
  • Ambience of woodburning fireplaces
  • Can burn on Air Quality Days

Natural gas log sets are less expensive to purchase and provide the aesthetic effect of flames, but they do not provide the benefit of heat. The gas log sets are made from a ceramic material that simulates the look of wood logs and are placed into an existing fireplace. Because the units use an existing space they are the least expensive to install. Natural gas log sets cost approximately $1000, plus the cost of installation.

Natural gas fireplaces/inserts are designed to provide heat. These models are self-contained and can be installed as a freestanding fireplace or into an existing fireplace. Inserts enclose the gas logs with a glass panel. As the logs “burn,” the glass heats up and radiates warmth. Some models have forced-air fans to improve heat distribution.

The cost for natural gas fireplaces/inserts ranges from $1,400 to $3,000, plus installation. Installation cost varies depending on the amount of work needed to vent the appliance and add a gas line. The higher the purchase cost of the appliance, the more “real” the gas logs appear and the greater the heat and energy efficiency.

Use only licensed installers and make sure that outside combustion air is provided with a safety pilot device. If natural gas lines are not accessible, propane models are also available and burn as clean as natural gas.


Coal burning gives off considerably more pollutants than burning wood or natural gas. In most coal appliances, the coal is burned in layers on the bottom of the furnace or on a grate. As the coal burns, pollutants such a particulate matter, sulfur oxides, carbon monoxide, and nitrogen oxides are given off.

Coal burning is allowed only in a stove designed for burning coal. It is not permitted in a woodburning stove. Coal burning is not allowed on RED days. Contact your local building department for building code information and permits. Link to more information about air pollutants.

 Related Links


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