The signs of a chimney fire are a loud roar or popping from the flue, flames or dense smoke shooting from the chimney top, and an intense, hot smell. If you notice any of them, get everyone out and call 911.
Other signs show up only after the fire, on the chimney itself. Either way, the chimney stays out of use until it has been inspected, and any damage is repaired before the next fire.
Which Signs of a Chimney Fire Can You See, Hear and Smell?
While it burns, a chimney fire can be heard, seen and smelled:
- A loud roaring from the flue, which a fire safety handout from Lincoln County, North Carolina, compares to a freight train.
- Flames or dense smoke shooting from the top of the chimney, sometimes with burning pieces of creosote landing on the roof.
- Loud cracking or popping and an intense, hot smell, which the Livermore Fire Protection District in Colorado lists among its warning signs.
Do not wait to be sure. The Lincoln County handout says not to hesitate and to leave immediately.
Signs of a Chimney Fire Found Afterward
Other signs turn up later, on the chimney itself. The Countryside Fire Protection District lists these as warning signs of a chimney fire:
| Where to look | What a past chimney fire can leave |
|---|---|
| Inside the flue | Puffy creosote with rainbow-colored streaks, swollen beyond its normal form |
| Inside the flue | Cracked or collapsed flue tiles, or tiles with large chunks missing |
| Damper and connector pipe | Warped damper metal or warped metal connector pipe |
| Top of the chimney | A discolored or distorted rain cap |
| Roof and ground | Flakes or larger pieces of creosote |
| Outside a masonry chimney | Cracks in the exterior masonry |
Some of these sit inside the flue, out of sight from the room. A Level 2 inspection adds a video scan of the flue interior, to catch damage that is not visible from the firebox or rooftop.
What Should You Do During a Chimney Fire?
Get everyone out of the house, then call the fire department on 911 from a safe distance. Do not try to put the fire out.
That is the advice of the Lincoln County handout. It warns that fire "can flash right through the house with incredible speed."
- If you can do it on your way out, close the stove's door and air inlets. Page 26 of our Class A installation instructions says to close all appliance air inlets. Do not stay to do it.
- Get everyone out of the house at once.
- Call 911 from a safe distance, such as a neighbor's house or your car.
- Leave the fire to the fire department. Do not try to put it out yourself.
- Do not light the stove or fireplace again until the chimney has been professionally inspected and any damage repaired.
Is It Safe to Let a Chimney Fire Burn?
No. The same handout says a chimney fire can crack open the flue liner and the chimney and spread to the structure of the house. Putting it out is the fire department's job, so leave the house and call.
What Causes a Chimney Fire?
Creosote is the usual cause. The Countryside Fire Protection District says most chimney fires are caused by creosote, the deposit wood smoke leaves on the flue wall.
Page 26 of our Class A installation instructions says: "When ignited, this creosote makes an extremely hot fire, known as a chimney fire."
Creosote builds up faster when the smoke runs cool. Our guide to creosote buildup names the causes, among them wet wood and a stove damped down to smolder. It also shows how to judge a deposit.
What Happens After a Chimney Fire?
The chimney stays out of service until it has been inspected. Our guide to chimney flue cleaning says to keep the system out of service until a qualified chimney professional has inspected the complete chimney and nearby structure.
Which Inspection Do You Need?
A Level 2 inspection. Our inspection guide lists a chimney fire among the reasons for a Level 2 chimney inspection. It says even a small chimney fire calls for one before the system is used again.
Level 2 covers everything in Level 1 plus a video scan of the entire flue, looking for cracks, gaps, liner damage and hidden blockages. It also checks the accessible attic and crawl spaces around the chimney.
What Do Our Warranty and Instructions Say?
Both ask for an inspection before the next fire. Our warranty page states: "In the event of a chimney fire, the system must be inspected and approved by a certified chimney sweep before reuse."
The warranty also asks for maintenance and inspection records, completed and signed by a certified chimney sweep, on the warranty card that comes with the product. Keep the sweep's report from after the fire with that card. Our Class A warranty terms set out the other conditions, and list chimney fires among the exclusions.
Page 26 of the installation instructions, under In Case of Fire, says: "If a chimney fire occurs, close all appliance air inlets, and call your local fire department. Do NOT use the chimney again until it has been inspected for possible damage."
Our Class A pipe is rated for 1000°F (538°C) in continuous use. The 2100°F figure in its UL 103 HT listing is a simulated chimney-fire test, not a temperature it runs at day to day. Passing that test does not replace the inspection after a real chimney fire.
What if the Inspection Finds Damage?
On a Class A chimney, replace the damaged sections with parts from the same Class A system as the rest of the chimney.
Systems from different makers are not interchangeable: each has its own locking mechanism, insulation thickness and outer diameter, and mixing them voids the certification.
If your chimney was built with our Class A chimney pipe, replace damaged lengths with matching 6 or 8 inch sections of the same range.
Where the whole run has to come out, a wood stove chimney pipe kit brings the matched parts for one route together. Each kit is configured to the height of your run, and our kits page names replacing a damaged or corroded chimney as one of the times a complete kit is needed.
On a masonry chimney, the Lincoln County handout says that after a chimney fire the chimney will need to be repaired and probably relined to make it safe for further use. The Level 2 inspection shows what yours needs.
What Should You Pay for First?
The inspection, before any parts. Only the inspection shows which sections are damaged, and the instructions say not to use the chimney until it has been inspected. Then send us the inspector's findings and your measurements for a free flue design, and we send back a personalized solution for the repair.
Buying a House With Signs of a Past Chimney Fire?
Ask for a Level 2 inspection before you buy. Our inspection guide names buying or selling a home, and a chimney fire, among the reasons for one.
- Look for the signs in the table above: warped metal, a distorted cap, creosote flakes on the roof, cracked masonry.
- Ask the seller for any chimney sweep or inspection reports, and whether the chimney has had a fire.
- Have the inspection report in hand before you agree on a price.
How Do You Prevent Another Chimney Fire?
Keep creosote from building up, and check for it often. These steps come from the chimney's own instructions, the U.S. Fire Administration and the U.S. Environmental Protection Agency:
- Inspect the chimney at least once every 2 months during the heating season, as page 26 of the Class A instructions advises, and remove any creosote or soot that has built up.
- Have the chimney inspected and cleaned each year by a professional, as the U.S. Fire Administration advises.
- Burn dry, seasoned wood. The U.S. Environmental Protection Agency says wood burns best at a moisture content of less than 20 percent.
- Build hot fires. The EPA says that for most appliances a smoldering fire is not safe or efficient.
- Sweep our Class A chimney with a plastic or poly brush, never a steel brush, as page 26 of its instructions says; on any other chimney, use the brush its maker approves.
What Should You Ask the Inspector?
Ask about certification, the standard and level of the inspection, liability cover, a written record and the warranty card:
- Are you certified by CSIA (Chimney Safety Institute of America) or NFI (National Fireplace Institute)?
- Does your inspection follow the NFPA 211 standard for chimneys, and is this a Level 2 inspection with a video scan of the flue?
- Do you carry liability cover for your work?
- Will I get a written record of the defects you find?
- On a Class A chimney from us, will you sign the inspection record on its warranty card?
Where Do You Find a Qualified Chimney Sweep?
Start with CSIA, which keeps a directory of certified professionals in the United States. Our warranty asks for a certified chimney sweep, so check the certification before you book.
Need More Information?
Our FAQ covers chimney pipe clearance requirements, flue temperatures and sizing. Each route is set out step by step in our chimney pipe installation guides.
To plan a repair or a new run with someone, ask a flue specialist or call 888-834-0880.
