Chimney Cleaning near you

Wood smoke carries unburned gases, moisture and fine particles. As it rises and cools in the flue, part of it condenses on the walls as creosote, a black or brown deposit that can be flaky and sooty, sticky and tarry, or hard and glazed. The Quebec government points out that these deposits are highly flammable, and a chimney fire that ignites them can crack the liner and damage the masonry or metal around the flue.

Creosote builds up fastest when the fire smoulders: wood that isn't dry, an air supply turned down too far, or a flue that runs cold, such as an oversized chimney or one on an outside wall. Health Canada recommends burning only dry, seasoned wood that has been cut, split and stacked in a dry place for at least six months, and Quebec's government warns against restricting the air too much. Good habits slow the buildup, but they don't replace sweeping.

A chimney fire can be loud and dramatic, or slow and quiet enough to go unnoticed until the next sweep finds its traces. Watch for these signs.

No single interval fits every home, because the buildup depends on how much wood you burn, how dry it is, the appliance and the chimney itself. Start with the appliance manufacturer's instructions and the findings of the last sweep or inspection, then adjust: a sweep who finds heavy deposits may suggest coming back sooner.

Official guidance sets the minimum. Health Canada advises having the chimney inspected by a qualified professional at least once a year and cleaning the chimney and flues regularly, following the manufacturer's instructions. The Quebec government recommends sweeping at least once a year, ideally in spring. Montreal's fire department says a chimney needs sweeping after every two cords of wood burned, or as soon as creosote on the flue walls is thicker than 3 mm. If you heat mainly with wood, that can mean more than one sweep a season.

A proper sweep is more than running a brush up the flue; it's also an inspection. Hard, glazed creosote doesn't come off with an ordinary brush, so the sweep may recommend specialized tools or treatment and a return visit.

An uncapped chimney is an open invitation. Birds, squirrels and raccoons nest in flues, and leaves and twigs can pile up on the smoke shelf over a summer. A blocked flue can push smoke and combustion gases back into the house the first time you light the appliance, so a sweep or inspection before the heating season is a good habit when the chimney has sat unused for months.

A properly sized chimney cap with a mesh screen keeps out animals and most debris, sheds rain and acts as a spark arrester. The mesh can itself clog with creosote or leaves, so the sweep should check it at each visit. If an animal is already inside, don't light a fire to drive it out: call a sweep or a wildlife control service that knows how to remove it humanely and within wildlife rules.

In Quebec, the government recommends having the chimney swept by a professional who holds the appropriate licence from the Régie du bâtiment du Québec, and having the system inspected by a professional every year. You can check a licence number on the RBQ website before booking.

Elsewhere in Canada, many sweeps and inspectors train through WETT, the non-profit that acts as the national registrar for wood-energy professionals. Ask what training and designation the sweep holds, whether they carry liability insurance and whether they provide a written report, which your insurer may want to see. That report is also the starting point for any repairs by a mason or chimney contractor.