Chimney sweeping: how often, and is it required?

Inspect every year. Sweep when the inspection says so.

The answer in 2 lines. There's no single federal law, but the national fire code standard, NFPA 211, and the Chimney Safety Institute of America say chimneys, fireplaces and vents should be inspected at least once a year and swept when needed. Some cities and states add their own rules, and your insurer or landlord may too. Get it done before your first fire of the season, burn only dry wood, and keep the sweep's report.

The first 3 steps

Book an inspection before the first fire of the season.
Ask for a written report and keep it with your insurance papers.
Burn only dry, seasoned wood: never trash, cardboard, painted or treated wood.

Stop: danger

Chimney fire (loud roaring, a hot chimney, flames or sparks out of the top, thick smoke): get everyone out and call 911. If you can do it safely on the way out, close the stove's air control.
A blocked chimney (nests, debris, collapsed liner) can push smoke and carbon monoxide into the home. Every home with a fireplace or stove needs working smoke and CO alarms.
"Creosote sweeping logs" don't replace a professional inspection and sweep.

What the rules say

National standard: NFPA 211 says chimneys, fireplaces and vents should be inspected at least once a year and cleaned, maintained and repaired if necessary. CSIA follows the same rule (CSIA FAQs).
No federal law requires homeowners to sweep their chimney. Some states and cities adopt NFPA 211 in their fire or building code, and some require an inspection when a home is sold or a new stove is installed. Ask your local fire department or building department.
Insurance: policies don't usually name a sweeping frequency, but a fire caused by poor maintenance can lead to questions. Keep your reports.

How often in practice

Wood stove or fireplace used a lot: an inspection every year, and a sweep whenever the inspection finds buildup. CSIA says a sweep is needed when there's 1/8 inch of soot buildup, sooner if there's glazed creosote.
Occasional fires: still a yearly inspection: animals and debris block chimneys even when you don't use them.
Gas, oil and pellet appliance vents: they need yearly checks too, usually during the appliance's service.

How to choose a chimney sweep

Look up certified sweeps near you: CSIA certified sweep search. CSIA certification means the sweep passed an exam on codes and standards.
Ask for proof of liability insurance, references, and what level of inspection they'll do (CSIA describes levels 1 to 3).
Get the price up front and a written report with photos. Be wary of door-to-door "inspections" that suddenly need thousands in repairs: get a second opinion. CSIA's tips: Hiring a chimney sweep.

Who pays

Homeowner: you do.
Renters: chimney upkeep is usually the landlord's, but check your lease and local law. Ask in writing before using a fireplace you're unsure about.
Condo or co-op: shared chimneys are often handled by the association; check your bylaws.

In Denver, Sarah rents a house with a wood stove. Before the first cold snap she emails her landlord, who books a CSIA-certified sweep. The sweep finds a bird's nest at the top and soot buildup, cleans the flue and leaves a report with photos. Sarah keeps a copy with her renters insurance policy.

A made-up story, for illustration.

Good to know

Heating equipment, including fireplaces and chimneys, is a leading cause of home fires. The U.S. Fire Administration's latest published trends cover 2014 to 2023; figures for more recent years aren't published yet.
Dry wood (20% moisture or less, says EPA Burn Wise) leaves less creosote. A moisture meter tells you; see our wood stove guide.
As of November 1, 2026, no nationwide sweeping frequency is set by federal law: local rules vary.

Bobby

Sources, verification, confidence

Verified on November 1, 2026, for the United States. Confidence: high for the NFPA 211 and CSIA yearly inspection standard and the chimney fire steps; medium for local requirements, which vary by state and city. This guide describes common cases, not a diagnosis.