Wood heating has been popular among Quebecers for many years, both for the ambiance and the comfort it provides. Province-wide, one in five homes has a wood-heating system. However, these systems can pose a fire hazard.

According to Public Safety, chimney fires accounted for 14.3% of all building fires reported to the ministry in 2018. Improper installation or use of wood-burning heating appliances is also a fire hazard.

Installation of Appliances

For masonry fireplaces and chimneys, the Quebec Construction Code (the Quebec adaptation of the National Building Code of Canada) establishes the criteria for safe installation.

The Code for the Installation of Solid Fuel Appliances and Related Equipment (CAN/CSA-B365) sets out the requirements for the installation, modification, and maintenance of solid fuel appliances, such as stoves and prefabricated fireplaces. This code specifies that certified appliances and components must be installed in accordance with the manufacturer’s instructions . In the event of a discrepancy with the code, the manufacturer’s instructions take precedence.

Thus, when installing certified prefabricated fireplaces, it is required to always follow the instructions in the specific fireplace manual, as each appliance has its own unique characteristics. Even the list of approved prefabricated chimneys will be included in the fireplace manual.

In short, no modifications should be made to this installation unless specifically indicated in the manufacturer’s manual. This same code stipulates that the installer is responsible for explaining to the user or owner how to operate the appliance and for ensuring that the manufacturer’s instructions are provided to them.

Use of the Appliances

Using high-quality, dry firewood reduces the likelihood of creosote buildup (a solid deposit formed by smoke resulting from incomplete or improper combustion of wood). Ignition of accumulated creosote could result in a chimney fire. To minimize creosote buildup, it is recommended to let firewood dry for one year in a location protected from the elements. Never burn household waste or construction debris, as the appliance has not been tested for use with such materials.

Prefabricated fireplaces must be used with the door completely closed, except when lighting the fire; otherwise, the temperature during operation may become too high. Some units require a log rack inside the firebox, while others do not. Therefore, consult the manufacturer’s manual for operating instructions. Furthermore, for units equipped only with a spark arrestor, the fireplace’s manual will specify whether the installation of doors is permitted, as well as the type of doors to be installed, if applicable. Under no circumstances is it permitted to use a fuel such as gasoline or kerosene to light logs or rekindle a fire.

As for densified (eco-friendly) logs, some of them contain no additives and can be used in a stove or fireplace. However, it is important to remember that a densified log has a higher heat output than a log of the same volume. As a result, some fireplace manufacturers specify a maximum number of logs to use per firing. Generally, logs containing additives or chemicals should not be used in heating appliances.

Maintenance of Solid-Fuel Heating Appliances

As for the appliance itself, user maintenance is often limited to a visual inspection and, if necessary, replacing cracked firebricks, a cracked glass window, or a damaged door gasket.

As for the flue system, creosote is the number one enemy. It clings to the inner walls of the connecting pipe and/or the chimney and is an excellent fuel that, once ignited, poses a high fire risk. Unfortunately, using products such as chimney cleaning logs or chemical additives is no substitute for professional chimney sweeping.

According to the National Fire Prevention Code, the chimney and flue must be swept as soon as creosote or soot deposits exceed 3 mm in thickness. Public Safety, for its part, recommends annual chimney sweeping, which we believe is the most common practice. Depending on usage, more than one sweeping per year may be necessary.

In our opinion, a chimney sweep—in addition to brushing the chimney with a brush of the appropriate size—must include an inspection of the heating system’s condition as well as the removal of residue from the appliance.

Furthermore, municipalities have the authority to regulate chimney sweeping within their jurisdiction and to require, for example, that chimney sweeps hold the chimney sweeping technician certification issued by the Association des Professionnels du Chauffage (APC).

Hot Ashes

According to Public Safety, an average of 140 fires occur annually due to the improper storage of hot ashes. They should be placed in a metal container with a raised bottom and a lid. The container should be placed outside the building on a non-combustible surface and at a minimum distance of one meter from any combustible material. It generally takes three to seven days for the ashes to cool before they can be disposed of with the trash.

During this period, the ashes should be stirred to ensure they are completely cooled.

Conclusion

The fire risks associated with using a solid-fuel heating appliance are very real. If you suspect that a fire may be attributable to the improper installation or use of such an appliance, we hope that the information provided in this article will guide you through your investigation.

Please feel free to contact us to speak with one of our fire investigation experts, who can provide strategic assistance in resolving your case.