How Often Should You Have Your Chimney Swept?

By The Mad Hatter Service Company · October 2026

The Short Answer: Inspect Every Year, Sweep as Needed

NFPA 211, the national standard for chimneys, fireplaces, and vents, recommends that chimneys be inspected once a year and cleaned as needed. In practice, most St. Louis and St. Charles homeowners who burn wood regularly need a sweep every year. Occasional burners and gas fireplace owners may not need a full sweep every year, but they still need the annual inspection.

At The Mad Hatter Service Company, every inspection is based on St. Louis City & County and St. Charles City & County currently adopted municipal code, and our routine chimney sweep always includes an inspection and an internal scan of the flue.

Why Annual Service Matters

Burning wood produces creosote, a tar-like residue that sticks to the inside of the flue. Creosote is highly flammable, and buildup is a leading cause of chimney fires. Even if you rarely use the fireplace, chimneys can be blocked by animal nests, leaves, and fallen flue tile, which can push smoke and carbon monoxide back into the home.

The St. Louis climate adds another factor. Freeze-thaw cycles every winter work water into cracks in the crown, mortar, and brick. An annual inspection catches small problems before they become expensive repairs.

How Often Based on How You Use It

• Heavy wood burners (several fires a week, or a wood stove used for heat): inspect annually, and expect a sweep every year or more than once per season.
• Occasional wood burners (a few fires each winter): inspect annually and sweep when the inspection shows buildup.
• Gas fireplaces and gas logs: annual clean and check of the burner, pilot, logs, and venting. See our gas fireplace service.
• Furnace and water heater flues: annual check, since these flues can deteriorate or become blocked even with no fireplace.

Signs Your Chimney Needs Service Now

• Smoke drifts into the room instead of going up the chimney
• A strong smoky or musty odor, especially in humid weather
• Black, flaky creosote in the firebox or on the damper
• Animal sounds or debris falling into the fireplace
• Water stains on the ceiling or walls near the chimney
• Pieces of tile or mortar in the firebox

When You Need More Than a Routine Inspection

NFPA 211 calls for a Level 2 inspection when a home is sold, when an appliance is added or changed, or after a chimney fire or storm. Our chimney inspection page explains each level, and every price is listed on our pricing page.

The Best Time to Schedule

Late summer and early fall are the best times to book, before the first cold snap fills the schedule. That way your fireplace is ready when you want to use it, and any repairs can be finished before winter.

Frequently Asked Questions