Traditional wood-burning fireplaces require little explanation in terms of their function and technology—these simple hearths are designed to burn wood and vent the resulting smoke and soot out of the building via a chimney and flue system.
Direct-vent fireplaces use more sophisticated technology, which we’ll cover, in detail, along with the advantages and disadvantages of each type of fireplace: direct-vent, vent-less, and wood-burning.
Direct-vent gas fireplaces are efficient and elegant alternatives to traditional wood-burning hearths. Their precision-designed fireboxes and versatile ventilation systems function by drawing fresh air, from outside, into the unit. Rather than burning wood, direct-vent systems use a variety of decorative, ceramic interior media such as logs, glass and stones.
Advantages: Direct-vent fireplaces are versatile and, with the right technology, can be installed in virtually any space, including bedrooms, bathrooms, kitchens, and finished basements as well as commercial lobbies, restaurants, bars, hotels and many more. These hearths heat spaces efficiently and evenly, eliminating drafts and cold spots.
Since combustion gases from direct-vent fireplaces are expelled outside the building, they do not present the air-quality problems and carbon monoxide dangers of wood-burning fireplaces and vent-less systems. Direct-vent systems that incorporate advanced technology, like those made by Ortal, are designed to disperse heat through the face of the firebox as well as the chaise. This ensures that the walls above and around the fireplace opening are cool to the touch while the room is still being heated efficiently.
This creates endless design opportunities—wall finishing materials, artwork, and items like flat screen TVs that cannot be used/placed around traditional masonry fireplaces, without restrictive precautions or assistance of a mantle, are suddenly on the table for designers.
Disadvantages: Direct-vent fireplaces can be more expensive to install than vent-less fireplace inserts, since they often require a gas line and electrical connection, as well as possible renovations, depending on the intended placement of the unit. The availability and cost of natural gas or propane on which direct-vent units operate can vary, particularly for those in rural areas.
Vent-less fireplaces are freestanding units fueled by gas or propane that don’t require a chimney or flue. They are typically sold either as inserts (firebox only) or as a “ready to use” unit, with a factory-built wood frame and mantle. They can usually be placed anywhere there is enough wall space and a gas line connection.
Advantages: Vent-less gas fireplace inserts are usually less expensive to purchase and install since they do not require the installation of gas lines or electrical connections. Portability is one of their main advantages—they can be placed anywhere there is an existing gas line, including inside an existing masonry fireplace (as long as it has a gas line).
Since they do not vent to the outside they heat spaces efficiently and produce low levels of combustion gases, so they are generally considered safe; however, there is some debate about their safety (see disadvantages below).
Disadvantages: Since they are not vented, the exhaust and moisture vent-less fireplace units produce remain in your home, increasing the risk of carbon monoxide exposure and reducing indoor air quality; in fact, some states, including California and Massachusetts, have banned vent-less gas/propane fireplaces.1
Gas and propane are more expensive than wood logs or wood pellets, so you’ll likely spend more heating your home if you use vent-less fireplace systems as a primary heat source.
Wood-burning fireplaces are typically either made of masonry (bricks or block, or stone and mortar) or are factory-built. Prefabricated wood-burning fireplaces consist of a lightweight metal firebox and metal chimney. Hybrid models combining a heavy metal firebox and smoke chamber that connects to an existing masonry chimney are also available.
Advantages: The sensory experience is the main draw of a wood-burning fireplace. The smell of burning wood, the distinctive crackling and snapping sounds, and the “dance” of the flame are nostalgic for many people. Wood-burning hearths can best be described as “warm and cozy,” and they provide a good (though often unevenly distributed) source of heat.
Disadvantages: Wood-burning fireplaces require a constant supply of wood, which is expensive and inconvenient, whether you chop it yourself, buy it at a store, or have it delivered. Approximately 80% of the heat produced by a typical wood-burning fireplace is lost through the chimney, making wood-burning hearths extremely inefficient.
Wood-burning fireplaces are messy, producing excessive ash that must be removed frequently, and creosote can build up in fireplaces and chimneys, presenting a fire hazard if not regularly cleaned by a professional.
Masonry fireplaces are massive structures that require extensive footing; even when constructed properly, earthquakes, foundation shifts, freeze/thaw cycles, and other natural events can cause cracking and structural problems. Although they are not as heavy as masonry fireplaces, prefabricated fireboxes are also not as durable, and they can begin to show problems within a matter of years if not installed properly.
In short, wood-burning fireplaces require a significant amount of regular maintenance and upkeep, and their disadvantages generally outweigh their advantages.
The Verdict: Direct-Vent Models Are the Superior Fireplace Choice
All things considered, direct-vent fireplaces are the safest choice and offer the most flexibility in terms of design options.
The sophisticated direct-vent fireplaces in Ortal’s collection are versatile, functional, and visually-stunning. Learn more about Ortal’s cool wall technology and heat barrier solutions, which open up a world of design possibilities for both professional and novice designers alike.