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Gas products
Today, more than 70 percent of all hearth products burn gas for fuel, according to the Hearth, Patio & Barbecue Association. Not only are gas appliances a highly efficient heat source, but they are easy to use as well: Lighting a fire requires no kindling, and can be as easy as clicking a remote control. Consequently, there is very little mess and virtually no maintenance.

If you have a wood-burning fireplace, converting to a gas product is relatively easy. Synthetic "logs" and gas inserts can be installed in existing masonry fireplaces. Freestanding gas stoves and factory built gas fireplaces can be added to new or existing rooms that lack a fireplace and chimney. If your home already has a gas line, installing a gas run to the fireplace location is easy and affordable; if not, however, it can be complicated and expensive to add a gas line to your home.
Now, it's time to examine some of your options for creating that perfect fireplace:
Wood Products

Wood stoves are an extremely efficient heating source for which you can expect to pay $1,000, for starters. Made out of plate steel or cast iron, these units are freestanding and must be placed a safe distance from walls. There are different settings to control how fast wood is burned and how much heat is generated. And no, they're not as smoky as they used to be! [CAPTION: Love the authentic quality of a wood-burning fire but concerned about the environment? The North Star wood-burning fireplace is exceptionally clean burning, and offers 78 percent efficiency and a heat output of 51,400 Btu/hr. Heat-n-Glo.]
Most new models come with catalytic combustors that lower the efficient burning temperature- which can be as high as 1,200 degrees- to about 600 degrees. The result is that smoke is burned off slowly, instead of being released as dirty, wasted fuel.
If your home has never had a wood stove, it will be necessary to install a chimney, which takes a few days and can be costly. If a chimney already exists, make sure the wood stove is compatible; consult an expert before making your purchase. Or, you might consider a factory-built fireplace, which is a great option for new constructionor an addition. These zero-clearance units are convenient and efficient, but require professional installation. They start at about $900.
If you already have a masonry fireplace and want to make it more efficient while still burning wood, you can install a wood insert for a cleaner-burning fire. Made of steel or cast iron with glass doors, these inserts vent through a metal liner that fits inside the chimney. These units start at about $1,200. As you shop, remember to look for the EPA sticker of approval and to check the Btu rating to make sure the product you select is appropriate for the size room you wish to heat.
Details, Details
All gas products are available in at least one of the following venting configurations:
Top-vented products vent through the roof by means of either an existing masonry or metal chimney, or a newly installed vent pipe. These units use oxygen from the room for combustion. While there is less heat loss from this method than from a traditional masonry fireplace, it is the least efficient option, as some heat is lost through the chimney. This type of fireplace or stove is best suited to new construction or single-story homes.
Direct-vented products are extremely convenient. There is no need for a chimney- the unit is simply vented directly through the wall behind it. Two pipes exit the back of the unit through the wall; combustion occurs when oxygen is brought into the unit through the outer pipe, while the exhaust is emitted through the inner pipe back to the outside. This allows for a great deal of flexibility, since direct-vented units can be installed just about anywhere- even under a window. Direct-vented appliances are also extremely efficient, as no heat escapes from inside the house through the vent.
Vent-free gas units have become increasingly popular over the past few years as technological innovations have made it possible to burn gas so efficiently and with so little waste that no chimney or vent is necessary- emissions can be released safely into the surrounding room. Installation costs are considerably reduced because no chimney is required. These units are also "zero clearance" which means that they can be placed next to other fixtures or structures without being a fire hazard. And no heat is lost through a vent, rendering these appliances almost 90 percent efficient.