Chimney cleaning: how often, cost and what a sweep does

Why chimney cleaning matters

Wood smoke leaves creosote inside the chimney: a black or brown residue that is highly combustible. If enough builds up, it can cause a chimney fire.² Sweeping removes the soot and creosote stuck to the flue walls, and a clean flue vents smoke and gases better, which also helps prevent carbon monoxide poisoning.¹

The inspection part of the visit matters as much as the brushing. Cracks in a chimney can let smoke into the house or expose chimney components to temperatures high enough to start a fire.⁴

How often should a chimney be cleaned?

The baseline on both sides of the border is once a year. The Quebec government says to have the chimney swept at least once a year, and more depending on the quality and quantity of wood you burn.¹ The US EPA's Burn Wise program (now an archived program) and fire officials recommend having the stove, chimney and vents professionally inspected and cleaned every year.²

Once a year is a minimum, not a guarantee. How fast a chimney fouls depends on the appliance and on how you burn.

When to book a chimney sweep

Spring is the recommended time. Deposits are still dry and easier to remove, and if the sweep finds a problem, you have time to make repairs before winter.¹ NRCan adds a second reason: deposits left in the system over the summer, combined with warm, humid air, can corrode steel parts. It recommends the most thorough cleaning and inspection just after the heating season, with summer also a good time to schedule maintenance before the first fall fire.³

Early fall also works, and the Ville de Québec calls a sweep at the start of fall an excellent habit.⁵ Keep in mind that most people wait until fall to book,⁶ so a spring or summer appointment keeps you out of the rush.

What a chimney sweep does

A professional sweep is more than a brush down the flue. The Quebec government lists the work a professional does, inside and outside your home:¹

1. Vigorous brushing of the chimney.
2. Checking the condition of the whole heating system.
3. Cleaning each component and adjusting parts.
4. Checking clearances around the appliance.
5. Reporting any breakage or deterioration.

NRCan describes the same job: a professional sweep cleans the entire system and reports any problems. They may suggest it is time to replace flue pipes, baffles, a catalytic combustor if you have one, or door gaskets.³

What a thorough chimney inspection covers

How much does chimney cleaning cost?

Government agencies do not publish chimney cleaning prices, and rates can vary from one contractor and region to another, so this guide does not quote a figure. What you can do is compare offers properly and keep the number of visits you need under control.

• Get two or three written quotes. Ask what each price includes: the inspection, the flue pipe, removing and cleaning the baffles, a written report, and how repairs are billed.
• Count the visits, not just the price. NRCan notes that chimney-cleaning costs can be significant for conventional systems that need cleaning two or three times each heating season.³ A low-emission stove that is run properly normally needs only one cleaning a year.³
• Burn well. Less creosote means fewer extra cleanings. Avoid green wood and an overly restricted air supply.¹
• Ask about help in the US. If you qualify for heating assistance, your local heating assistance office may also cover cleaning, repair or replacement of your wood heater and chimney.⁴
• Talk to your insurer. CAA-Québec notes that insurers often factor the number of cords burned into their rates.⁶

How to find a certified chimney sweep

In Canada, NRCan recommends having your unit inspected and cleaned at least once a year by a technician certified under the Wood Energy Technical Training (WETT) program or, in Quebec, by the Association des professionnels du chauffage (APC).³ The Quebec government also recommends a yearly inspection by an APC member, ideally before the heating season.¹ Look for a sweep who is trained, insured and certified, and note that your wood-heating retailer may offer sweeping and maintenance too.³

In Quebec, repair and construction work on wood stoves and factory-built chimneys falls under Régie du bâtiment du Québec (RBQ) licence subcategory 10.0, while masonry fireplaces and chimneys fall under subcategory 4.1.⁸ If the sweep recommends repairs, check that the contractor holds the right RBQ licence for that work.

In the US, the Chimney Safety Institute of America (CSIA) has a list of certified chimney sweeps searchable by state,² and the National Fireplace Institute (NFI) certifies hearth technicians through nationwide testing.⁴

Can you clean your own chimney?

Creosote sweeping logs and chemical additives never replace a professional sweep: they remove only part of the creosote.¹ They also do not detect structural problems, corrosion or the type of creosote in the flue.⁶

If you brush the chimney yourself, CAA-Québec recommends having the rest of the system checked by a licensed solid-fuel heating contractor, and having that contractor clean the venting system at least every three years.⁶ The US Consumer Product Safety Commission's advice is to never service fuel-burning appliances without the proper knowledge, skill and tools.⁷

Between professional visits, you can still do a few things yourself:

• Before the first fire of the year, look up the chimney with a small mirror and check that it holds no debris such as a bird nest or loose part, that the door gasket is not cracked, and that the outside of the chimney shows no rust or corrosion.¹
• On newer stoves, remove the baffles to clear the soot and ash that settle on them.⁶

After a chimney fire

Call the fire department.⁶ Even if the fire seems out, have the chimney inspected, and repaired if necessary, before using the system again.³⁶

Is chimney sweeping required where you live?

Rules depend on your municipality, and the Quebec government tells residents to check local regulations.¹ As an example, Québec City requires a yearly chimney inspection, with sweeping if needed, and a carbon monoxide alarm on every floor of a building with a wood fireplace.⁵ Call your town hall or local fire department to find out what applies to you.

Questions