Fireplaces get heavy use in Westlake Hills and the rest of the Austin area during our short but real burn season, roughly late November through February. That’s a small window compared to colder climates, which is exactly why chimney fires here tend to catch homeowners off guard — a chimney that only sees a few dozen fires a year can still build up enough creosote to become dangerous, especially when Ashe juniper (“mountain cedar”) is burned, since cedar smoke deposits resin-heavy residue faster than seasoned oak or mesquite.
What Actually Causes a Chimney Fire
Almost every chimney fire traces back to the same culprit: creosote. As wood burns, smoke, unburned particles, and tar vapor rise through the flue and cool against the masonry or metal liner, leaving behind a dark, sticky coating. That coating is flammable, and once it ignites inside a confined flue, it burns hot enough to crack liners, warp metal chimney caps, and in the worst cases spread into the attic framing.
Wood Choice Matters More in Central Texas
Because so many Hill Country properties have cedar growing right on the lot, it’s tempting to burn what you clear. Cedar burns hot and fast but leaves more resin behind than a properly seasoned hardwood. If you burn cedar, plan on more frequent inspections — not less.
Signs Your Chimney Already Has a Problem
- A loud, roaring or crackling sound coming from the flue during or after a fire
- Dense black smoke pouring from the top of the chimney
- Flakes of creosote or ash falling from the chimney onto the roof
- A hot, chemical smell that lingers well after the fire is out
If you notice any of these, treat it seriously: shut the fireplace doors or screen if you can do so safely, get everyone out of the house, and call 911. Never pour water on a hot chimney — the sudden temperature change can crack masonry that was otherwise structurally sound.
How to Keep It From Happening
1. Get It Swept and Inspected Annually
The Chimney Safety Institute of America and FEMA are both blunt about this: clean chimneys don’t catch fire. A trained sweep can see buildup and cracks you simply can’t from the living room. Homes in the Austin area that burn regularly through the winter — or that have a wood stove insert — should have chimney cleaning done every year, before the first cold snap.
2. Keep Fires Smaller and Hotter
Small, well-fed fires burn more completely and leave less residue than a flue stuffed full of logs smoldering at low heat. Use wood that’s been seasoned at least six months, and avoid closing the damper down too far — a starved fire is a smokier, creosote-heavier fire.
3. Never Burn Trash, Cardboard, or Wrapping Paper
It’s a classic holiday mistake. Paper and cardboard burn fast and send sparks and burning debris up the flue, which can ignite creosote buildup you didn’t know was there.
4. Dispose of Ashes Correctly
Ashes can hold enough heat to reignite a full day after a fire. Store them in a metal container with a lid, kept at least three feet from the house, deck, or any dry brush — a real concern here given how quickly Central Texas lawns dry out in a drought.
5. Install or Maintain a Proper Chimney Liner
A sound liner keeps combustion gases contained, improves draft, and protects the surrounding masonry or framing from heat damage. If your home is older or you’re not sure your chimney was ever lined, that’s worth having a professional check.
The Bottom Line
Chimney fires are preventable almost every time — the fixes are routine maintenance, not major renovation. Westlake Ducts Austin sweeps and inspects chimneys throughout Austin, Westlake Hills, Lakeway, Bee Cave, Dripping Springs, and the surrounding Hill Country. If it’s been more than a year since your last sweep, call us at (512) 598-4978 before you light the first fire of the season.