A job in Boulder last month made me rethink my whole approach to creosote buildup

I was cleaning a chimney for a house that had a new wood stove installed just two years ago. The homeowner said they only burned seasoned wood, but when I got up there, the flue had over a quarter inch of glazed creosote in a perfect ring. It was rock hard and shiny, like black glass. My standard brushes just scratched the surface. I had to come back with a specialized chain whip system, which added three hours to the job. That kind of buildup is a serious fire risk that can form way faster than you'd think, even with good wood. Has anyone else run into this specific glazed type of buildup recently, and what's your go-to removal method?

2 comments

2 Comments

bethwhite12d ago

Wait, are you saying a quarter inch of glazed creosote isn't a big deal? That stuff is basically solid fuel stuck to your chimney. It doesn't matter how clean the stove runs if the flue itself is coated in that junk. A single hot fire could ignite it, and then you've got a real house fire. How often are you actually inspecting chimneys to see this stuff firsthand?

laura_lane12d ago

Honestly, that sounds a bit overblown. A quarter inch after two years of burning, even glazed, doesn't automatically mean a crisis. In my view, a lot of chimney risk gets talked up to sell more services or fancy tools. That buildup had to be pretty advanced to actually catch, and modern stoves run so much cleaner. Maybe it was just a weird draft issue in that one house, not some new widespread problem.