Chimney sweep in San Francisco

A little of it is normal. Enough of it, built up over one or more seasons of occasional fires, is fuel sitting inside a chimney that occasionally sees temperatures hot enough to ignite it. A chimney sweep is the mechanical removal of that buildup: a brush sized to the exact diameter of the flue, run its full length from the firebox to the top of the liner, breaking the creosote and soot loose so it can be vacuumed out rather than left to accumulate visit after visit.

San Francisco’s mild climate means a lot of fireplaces here get lit occasionally through the cooler months rather than run daily the way a wood stove might elsewhere, and that occasional-use pattern is exactly what causes owners to underestimate how long it has actually been. Creosote does not need daily fires to accumulate to a dangerous level — it needs time, and an annual check is the only reliable way to know where a flue actually stands.

A brush pass loosens built-up creosote inside a confined flue, and if that debris were simply left to fall, it would end up on the hearth, the rug and everything nearby. We do not work that way. Floor protection goes down before the first brush stroke, covering the hearth and the walking path to it, and a HEPA-filtered vacuum stays sealed against the firebox opening for the entire brushing pass, pulling debris out as it falls rather than letting it settle. The room you leave for the appointment is the room you come back to.

Defined by NFPA 211, a Level 1 inspection covers everything a technician can see and reach without a camera or a ladder to the roof: the readily accessible interior of the flue, the firebox, the smoke chamber immediately above it, and the connection between the appliance and the chimney. It is the right depth of check for a chimney under continued, ordinary use with no recent changes to the appliance or any reason to suspect hidden damage.

If that visual check turns up something the naked eye cannot fully explain — a crack that might run deeper than it looks, or damage after an earthquake or a hard winter storm — we say so plainly and point toward a Level 2 inspection with a video camera, rather than guessing at what a brush and a flashlight cannot show.

A second flue, a wood stove with its own connector pipe, or a Victorian-era chimney with an unusually tall or narrow flue can extend that, and we will tell you before we start if the scope looks different from the baseline. What does not change is the sequence — protect, brush, extract, inspect, report — regardless of how many flues are on the property or how long since the last sweep.