Fire Safety Starts in the Chimney

Every year, thousands of homes are damaged and destroyed by fires that begin in the chimney. These fires also cause hundreds of injuries and fatalities. But homeowners and family members aren’t the only victims; hundreds of firefighters are also injured battling chimney fires. The alarming fact is that chimney fires are entirely preventable. For these reasons, fire safety starts with proper chimney maintenance.

A Silent Threat May Be Lurking in the Chimney

Chimney fires often occur when creosote, a tar-like residue from burning wood, accumulates in the chimney flue and ignites. Additionally, organic materials such as leaves, twigs, and bird nests clogging the flue can also start a fire in the chimney. These fires can flare up in two ways:

Chimney Fire in Progress

Characterized by loud cracking and popping, dense smoke, an intense hot smell, and sometimes even flames shooting from the chimney top. A chimney fire may be accompanied by a low rumbling sound, similar to that of a freight train. These are signs of a potential chimney fire in progress. Evacuate everyone from the house, staying clear of the driveway, and call 9-1-1 immediately.

Slow-Burning, Undetected Fires

These fires are small and typically burn themselves out, often remaining unnoticed until a professional chimney inspection reveals the presence of a previous fire. However, these small fires can reach extreme temperatures of up to 2000°F! This extreme heat can damage and weaken the chimney liner without immediate visible signs.

What Causes Creosote Buildup?

According to the Chimney Safety Institute of America (CSIA), 1/8” or more of creosote is dangerous and must be removed. Several factors contribute to the hazardous accumulation of creosote:

• Insufficient Draft: This can occur when glass doors are closed, the damper isn’t fully open during fireplace lighting, and there’s insufficient oxygen to maintain a fire. For wood stoves, closing the stove damper or air inlets too much also restricts airflow, resulting in smoke and increased creosote accumulation.
• Unseasoned Wood: Burning wood with high moisture content results in incomplete combustion, which promotes more condensation and creosote formation within the flue.
• Overloading the Firebox: Overloading the firebox with too much wood can prevent the temperatures from rising high enough to burn the logs effectively. An excess of logs acts as an insulator, and the cooler temperature contributes to increased creosote buildup.
• Cold Chimney Syndrome: Starting a fire in a cold flue can cause a backdraft that not only pushes smoke and soot out of the fireplace but also creates more creosote residue from incomplete combustion.

Warning Signs Your Chimney Had a Fire

Is your chimney showing signs of a previous fire? It’s vital to be aware of these subtle but significant warning signs that indicate a chimney fire may have occurred, requiring immediate professional inspection:

1. “Honeycomb” Creosote: This type of creosote residue is a clear sign that your chimney had a fire. This expanded residue, which resembles a honeycomb, is highly flammable, and its continued accumulation can obstruct the flue, increasing the risk of fire and carbon monoxide poisoning.
2. Cracked Flue Tiles: Intense heat can cause the clay flue tiles to crack, chip, or even burst, increasing the risk of the next chimney fire spreading to other areas of your house.
3. Scorched Components: Damper plates, smoke chamber baffles, or even the top of a metal chimney cap may show signs of heat stress, such as warping, scorching, or discoloration.
4. Discolored Chimney Cap: A discolored chimney cap, especially if it’s dark black or damaged, could be a sign of a previous fire.

If you suspect your chimney had a fire, stop using your fireplace or stove immediately and contact a certified chimney sweep for a thorough inspection.

Fire Safety Starts with Thermocrete® Chimney Liners 

Protect your home and enjoy a safer fire-burning experience with a Thermocrete® chimney liner. This advanced solution outperforms traditional steel liners and is backed by our lifetime warranty. Thermocrete® is exclusively available for professional installation, ensuring it meets the highest safety standards. Contact us to locate an Approved Industries certified installer near you and discover the fire safety benefits of a Thermocrete® chimney liner.