Wood Stoves Installed in Residential Garages / WETT Inspections™

By Ian Myers

Having the right and ability in Canada, under CSA B365 Installation code for solid-fuel-burning appliances and equipment, to install a wood stove into a residential garage may not be much of a concern for urban communities, but for many rural areas it is an important option.

The following are two, notable, additional requirements, while installing in a residential garage, that are not required when installing within a residential dwelling.

The applicable clause: 4.3 Hazardous Locations

An appliance shall not be installed in a location where a corrosive atmosphere, flammable gas or vapour, combustible dust, combustible fibres might be present. It may be installed in a

(a) storage or residential garage, provided that the appliance is mounted in such a manner that any component representing a source of ignition, such as a blower or bottom of the firebox, is at least 450 mm (18'') above the floor level and protected against physical damage.

Naturally, should a significant amount of flammable liquid be spilled within the garage (such fumes being heavier than air) having the air intake of the wood stove at least 18'' above the floor would help to prevent fumes from immediately being drawn into the fire box of the wood stove causing an explosion or fire. The additional “protection from physical damage” (such as a pole or curb in front of the appliance) should the stove be installed, in-line, such that it could be struck by a moving vehicle — would further contribute to the over-all safety of the installation.

These are all “well and good,” positive installation instructions. However, it does contain a contradiction, that from my experience results in a percentage of WETT inspectors declaring while inspecting that wood stoves in garages are “non-compliant,” beginning with the title of such installations being 'Hazardous Locations' and the introductory sentence declaring a hazardous location to be defined as a place where “flammable gas or vapour might be present.”

I am on the CSA B365 Technical Committee and I brought this topic up at our last meeting and requested that this wording be changed.

My rationale for the change, essentially is that it is a contradiction, as evidenced by what is not an unreasonable reading of the current Code. If an installation location was dangerous then CSA B365 would not be advising how to proceed.

Further, as installers and inspectors, using the Code — we do not assume responsibility for potential use or operation of that which has been installed or inspected, we do not inspect for “potentials,” if we did, then no appliance of any type would be installed anywhere.

I also said, that I understand and respect the message behind the current composition, but that education regarding usage, including the space where an appliance is located should best occur by other means. For example: the new WETT inspection forms have a page regarding Fire Codes, for educational purposes, plus there is an inspection point referring to the Hazardous Locations clause; this would be an excellent place to educate the public, with an additional, specific note for the user of the appliance which has just been installed or inspected, all the more reason for insurance companies to request a current WETT Inspection™ for wood-burning systems.

So, my suggestion was a simple one, that the word be changed from “might” be present, to – “is” present. By all means, while inspecting, if fumes or large amounts of combustible dust are present it should be noted as “non-compliant” in the Hazardous Locations category.

It is important to note, that gas and solvent containers being present in a garage are not hazardous. The design of such containers are also governed by Codes, up to and including how many units can be stored at one location. The analysis of such factors is outside of the expertise and definition of a WETT Inspection™.

It is important to clarify and amend the wording of our Codes in response to their “real-world” use. We certainly do not want them to be applied in an unintended way.

It is important that rural areas continue to have the option of a solid fuel burning appliance in their garage and our industry should protect that right.