CREOSOTE & CHIMNEY FIRES A chimney is designed to expel by-products of combustion. As these substances exit a fireplace and flow up a relatively cooler chimney condensation occurs. When condensation and chimney gases combine, a residue called creosote forms. Creosote can be tar-like or flaky and can be shiny in appearance.
Creosote is highly flammable. If enough creosote builds up inside a chimney, a chimney fire can occur. Different conditions can accelerate creosote buildup — restricted air supply, cooler than normal chimney temperatures and unseasoned wood. All these can contribute to a dangerous situation if left unattended.
A chimney fire can do extensive damage to a chimney and/or a home. A chimney fire can be very loud and last for an extended amount of time depending on the amount of creosote buildup. A chimney should be regularly inspected and cleaned by a professional. When is the last time your chimney was cleaned?
DAMAGE CAUSED BY CHIMNEY FIRES Masonry Chimneys
A chimney fire can reach upwards of 2000° F. At this temperature mortar can "melt", tiles can crack, or the inner liner of the chimney can collapse. Most often tile crack and mortar is displaced. When this occurs flames can find their way to the walls of a home. After one chimney fire the home may be fine, but if another one occurs the home can be burnt to the ground.
Pre-fabricated Metal Chimneys Metal pre-fab chimneys are designed to withstand extreme heat. Under certain chimney fire conditions damage can still occur. Seams and/or components may buckle or warp. When pre-fab metal chimneys are damaged by fire they must be replaced.
Build smaller, hotter fires that produce minimal smoke
Never burn trash
Have the chimney inspected and cleaned regularly
PROPER MAINTENANCE
If your chimney is clean it won't catch fire. Be sure to have a certified chimney sweep inspect and clean your chimney annually.
HAVE YOU HAD A CHIMNEY FIRE?
Since chimney fires range in intensity you may not know that you've had one. Here is what a chimney sweep looks for during an inspection:
"Puffy" creosote with rainbow colored streaks that have expanded beyond creosotes normal form
