How to Care for Your Wood Burning Fireplace
To avoid the buildup of smoke and soot, it is crucial to maintain proper ventilation and carefully select appropriate firewood. By adhering to these guidelines and incorporating other recommended practices, your wood-burning fireplace will provide a warm and comfortable source of heat throughout the winter season.
Wood burning fireplaces have an enchanting ability to transform any space into a warm and inviting haven. Whether nestled in a quaint cottage or gracing the heart of a modern home, these hearths provide a comforting refuge from the chill of winter or simply a soothing backdrop for moments of relaxation. The gentle crackle of burning wood and the soft hum of flames dances in harmony with the flickering light, create a mesmerizing ambiance that encourages serenity. It’s no wonder that fireplaces continue to be cherished as timeless symbols of warmth and contentment in our homes.
SAFETY
Improper installation, operation, or maintenance of wood-burning fireplaces can pose significant risks of house fires. Hazards such as embers escaping from an unscreened fire, or chimney fires resulting from creosote build-up can be avoided through proper care and usage. Additionally, wood-burning fireplaces have the potential to compromise indoor air quality. According to Burn Wise, a program under the US Environmental Protection Agency, while the aroma of smoke may be pleasing, it is detrimental to one’s health. Any instance of smoke escaping from the firebox into the room indicates a malfunctioning fireplace. Furthermore, since fires consume a considerable amount of indoor air during combustion, there is a possibility of creating negative air pressure inside the house, which can lead to outdoor air being drawn indoors to replace the consumed air. If this replacement air is pulled in through the flues of gas or oil-burning furnaces and water heaters, it may carry harmful flue gases like carbon monoxide back into the home, a phenomenon known as “back-drafting.” Hence, it is imperative for all homes to have functional and well-maintained smoke and carbon monoxide alarms.
COMPONENTS OF FIREPLACES AND CHIMNEYS
The majority of wood-burning fireplaces are constructed using sturdy masonry materials on solid foundations, complemented by masonry chimneys. Alternatively, some fireplaces are factory-built and incorporate specialized triple-wall stainless steel chimneys.
Among the prevalent masonry fireplace designs is the “Rumford” fireplace, named after the 18th-century British Count Rumford, credited with its development. Rumford fireplaces represented a significant advancement over earlier designs, excelling in both smoke extraction from the fireplace and room heating capabilities. Remarkably, the Rumford-inspired fireplace design has proven its durability over time, often outperforming even some of the more modern fireplace designs available today.
In a masonry fireplace, the firebox is meticulously constructed using specialized heat-resistant firebrick, while the interior of the chimney is lined with square clay tubes known as “tiles,” also designed to withstand high temperatures. The visible components of the chimney, hearth, and fireplace are typically crafted from non-combustible materials such as standard brick, stone, or tile. To protect against the elements, it’s common to cap the chimney with either a metal or stone slab, serving the dual purpose of keeping rain and snow out and preventing birds and animals from entering. Additionally, these chimney caps perform a safety function by acting as spark arresters, containing any embers that might travel up the chimney and preventing potential hazards.
A common feature in many fireplaces is a raised fire grate, typically constructed from cast iron. This grate serves to elevate the fire, facilitating improved airflow and combustion. Additionally, you’ll often find an ash-dump door located on the firebox floor, also made of cast iron. The ash dump door plays a practical role by enabling the easy disposal of cold ash. This ash is swept into a chamber located beneath the firebox, typically enclosed within the fireplace foundation in the basement. This basement chamber can be accessed through another small, snugly fitted metal door, allowing for the convenient removal of ash without any mess in the living area.
While the traditional masonry firebox is prevalent, some fireplaces incorporate specialized metal inserts to enhance wood-burning efficiency and cleanliness. These inserts often feature fans that help circulate air from the living area around the exterior of a sealed firebox, thereby significantly improving the fireplace’s ability to heat living spaces efficiently. This transformative function aligns the wood-burning fireplace more closely with the performance of a wood stove, making it a more effective and practical heating source for your home.
HOW IT WORKS
Before igniting a fire, the damper is opened to allow smoke and combustion gases to exit through the chimney. Once the fire is lit, the extremely hot combustion gases begin ascending the chimney due to convection. Simultaneously, the fire draws in air from inside the home for combustion. As the flames stabilize, the hot and potentially harmful combustion gases continue to be drawn upward and out of the chimney’s top, while fresh air is pulled in for combustion, maintaining the fire.
After the fire has extinguished, and the ashes have cooled completely, the damper is closed to prevent unnecessary heat loss from the home. At this point, the ashes can be removed from the firebox or deposited into the ash dump through a door typically found in the floor of a masonry fireplace.
According to the CSIA’s Eldridge, open fireplaces are generally not efficient space heaters because the chimney draws not only the hot combustion gases but also conditioned air from the home, resulting in a cold and drafty house. To address this issue, a pipe can be installed to bring in make-up air directly from outdoors, avoiding both the discomfort of air infiltration through cracks and gaps and the potential danger of back-drafting due to insufficient available combustion air.
For added safety and control over airflow, glass doors can be installed on fireplaces. This provides an extra layer of protection while regulating the fire’s oxygen supply. However, even with glass doors, a fireplace still has relatively poor heating efficiency. To improve efficiency, homeowners can opt to install a high-efficiency, EPA-approved metal fireplace insert, effectively transforming the fireplace into a cleaner and more efficient heat source akin to a wood stove. This modification not only enhances heating performance but also helps reduce heating expenses.
MAINTAINING A WOOD-BURNING FIREPLACE
Maintaining a wood-burning fireplace involves several essential steps. First, once the fire has completely extinguished, and the ashes have cooled, you should either use the ash dump or remove the ashes directly from the firebox. These ashes can serve as a valuable source of plant nutrients and can be sprinkled onto flower beds or added to compost piles.
The most crucial aspect of fireplace and chimney maintenance is regular chimney sweeping and an annual inspection. Over time, soot and creosote, which are byproducts of inefficiently burning fires, can accumulate within the chimney. When this buildup becomes substantial, it can pose a serious fire hazard, known as a “chimney fire.” Explaining the potential devastation of a chimney fire, Eldridge highlights that everything above the damper is not designed to withstand fire but only hot smoke and gases, making a chimney fire highly destructive. Chimney sweeping should occur when creosote buildup reaches 1/8 inch or more and at the end of the season, ideally before summer to prevent the formation of acidic compounds resulting from the combination of creosote and humidity, which can damage masonry and lead to unpleasant odors.
During chimney cleaning, precautionary measures are taken to protect the chimney sweep from inhaling harmful soot and creosote dust. A drop cloth is laid down on the hearth and extended into the room, and a respirator is worn. Metal or plastic chimney brushes and specialized tools, along with a vacuum system, are employed to remove soot and creosote from the chimney’s interior walls and damper ledge. The chimney cap is also inspected and cleaned of creosote deposits, and occasionally, a chemical cleaner may be utilized.
Simultaneously, as the chimney and fireplace are cleaned, a thorough inspection is carried out to ensure there are no significant cracks in the firebox, chimney, or liner. Loose or missing bricks or mortar are identified and addressed. The functionality of the damper is verified, as well as the condition of the chimney cap. Overall, the structural integrity of the chimney is assessed to ensure safe and efficient operation.
FIREPLACE MAINTENANCE TIPS
Install and Maintain Alarms: Ensure you have functional smoke and carbon monoxide alarms in place and regularly test them to guarantee your safety.
Clear Combustibles: Keep flammable materials like carpets, curtains, and furniture at a safe distance from the fireplace when it’s in use. Employ a protective guard to prevent children and pets from getting too close, and make sure there are no combustibles within 12 inches above the lintel, including wooden mantels.
Ash Removal: Regularly remove ash from the fireplace, especially when it accumulates at the bottom of the grate, as it can hinder airflow. Utilize safety gear such as a dust mask and gloves while performing this task.
Annual Inspection and Cleaning: Arrange for a certified chimney sweep to inspect and clean your wood-burning fireplace and chimney at least once a year, preferably at the end of the burning season. More frequent inspections may be necessary if you notice creosote and soot buildup exceeding 1/8 inch on the chimney’s interior. The Chimney Safety Institute of America offers a directory of certified chimney professionals across the United States.
Functional Test: Periodically test your fireplace’s functionality by lighting a few small pieces of well-seasoned wood from the top down. If you observe smoke entering the room instead of exiting vertically into the chimney, promptly investigate and rectify any issues. Potential problems may include creosote or soot buildup, obstructions like bird or animal nests in the chimney, a partially closed damper, or the use of wet, inefficiently burning wood.
Use Seasoned Wood: Burn only seasoned wood, not “green” wood. Seasoned wood has been cut and dried under shelter for at least 6-12 months, registering less than 20 percent moisture content. Split wood dries more effectively and burns more efficiently than whole logs. You can identify well-seasoned wood by the sharp, ringing sound it makes when two logs are knocked together, in contrast to the dull thud produced by green wood. Burning green wood results in incomplete combustion, increased soot, and creosote buildup.
Choose Hardwoods: Opt for burning hardwoods like oak, ash, and maple over softwoods like pine, poplar, and cedar. Hardwoods are denser and heavier, providing more heat output and efficiency compared to lighter softwoods.
By following these fireplace maintenance guidelines, you can enjoy a safer and more efficient heating experience while preserving the longevity of your fireplace and chimney.
