We recently did a Level 2 Cleaning and Inspection for a buyer of a beautiful new home – at least new to the buyer!  Unfortunately, they were very concerned about the fact that the home had a fireplace, yet had no chimney.  No chimney, you ask?  Yes, no chimney.

One of our favorite things to do is educate clients about fireplaces and chimneys, so we were glad to have this opportunity to share what we know about ventless fireplaces, which are becoming more common in the Jacksonville area only recently despite having been sold in the United States since 1980.

Unvented fireplace systems can also be called chimney-less fireplaces or duct-free fireplaces, and are typically fueled by natural gas, propane, electricity or even alcohol-based gels.  These appliances rely on indoor air for combustion; a chimney or flue isn’t necessary for it to function.  Ventless fireplaces are heavily regulated by federal agencies for safe operation in your home, but the debate still rages on – are they really safe?  Even though heavily regulated for safety, several states including California and Massachusetts have banned ventless systems (so have Canada and several other countries).

First the pluses of ventless fireplace systems…

These systems are growing in popularity, especially in the Northeast Florida area, because they are so easy to install.  Large builders like ventless systems mostly because they don’t have the design limitations of configuring a flue to the exterior – so they are also much cheaper to include as a feature of the home.  Another upside?  It can be located almost anywhere in the home without much effort.  In addition to these benefits, proponents also claim ventless fireplaces burn at nearly 100% efficiency (meaning they heat better) and release far less harmful gasses than most other portable heating alternatives.

Now for the downside of ventless fireplaces…

While traditional fireplaces (with chimneys) vent unburned airborne particulates and carbon monoxide (CO) from the fire out through the chimney, there is nowhere for an unvented gas fireplace to expel those items except into the indoor living space, right into the room where it’s located.  Most would agree this stuff is probably not good to breathe!  While there have not been any reported deaths from ventless gas fireplaces, in a worst case scenario, it is possible.  Electric fireplaces and alchohol-gel fueled fireplaces don’t emit carbon monoxide.

According to the International Association of Certified Home Inspectors (InterNACHI), “To mitigate CO dangers, manufacturers instruct customers to keep a window open while ventless gas fireplaces are in operation –- advice that is easy to ignore, as an open window allows the entry of cold air, defeating the efforts of the fireplace to warm the living space. Many manufacturers also install an oxygen-detection sensor (ODS) in their ventless fireplaces that will automatically shut down the appliance if oxygen levels in the home become dangerously low. Critics point out that this sensor is typically located at the lower part of the unit near the floor, where it detects cool, fresh, oxygen-filled air and misses hot combustion gasses as they rise and pool toward the ceiling. And if the sensor fails, any CO-producing abnormality experienced by the fireplace will continue unnoticed and potentially harm building occupants.”

The other less obvious but still important item to note is that ventless fireplaces create high levels of water vapor, which can lead to mold growth and a variety of other moisture-related building problems.  In addition to damaging carpeting, drapes, upholstery, books, photos, and building materials, mold can be a serious concern for at-risk individuals.  Again, according to InterNACHI, “The U.S. Department of Housing and Urban Development (HUD) bans ventless fireplaces in their housing, and advisements against the use of these appliances have been issued by various watchdog groups, such as the American Lung Association, the Centers for Disease Control, the Environmental Protection Agency, and even the Mayo Clinic.”

Bottom line for us at Chimney Champions – when a properly sized ventless fireplace (proper for the size of the room it’s located in) is installed and used according to the manufacturers instructions, it can and should be a source of pleasure in your home.  However, nothing is trouble-free, even though advertisements for these systems will often claim that very thing!  As with all fireplace styles, it should be respected by having it professionally inspected yearly and maintained appropriately.