Guides
Electric, Propane, or Gas: Heating a Garage Workshop in Canada Safely
Heating a garage workshop in Canada comes down to certification, carbon monoxide and provincial fuel codes. Each fuel asks something different.
What to take away
- Electric heat adds no carbon monoxide and suits a sealed garage, but it needs a dedicated 240 volt circuit and a permit.
- Propane suits a detached shop with airflow; the real constraint is cylinder storage, not the heater.
- Natural gas is usually cheapest to run and slowest to install, since only a licensed fitter can bring the line in.
- Certification, combustion air and a CO alarm decide whether any option is safe here.
What actually decides the choice
A Canadian garage is normally attached and unheated, and it was built around a car rather than a bench. That shapes the choice more than the fuel does. Insulation is thin, the overhead door leaks, and the slab sits close to grade, so heat leaves as fast as you make it.
Certification comes first. A mains-powered or fuel-burning heater sold in Canada should carry a mark from a body accredited by the Standards Council of Canada, such as CSA or ULC. CSA certification marks show an appliance was tested to a Canadian standard. A heater bought across the border can be legal there and uncertified here.
Combustion air comes second. A sealed garage with a propane heater will find makeup air somewhere, rarely where you would choose.
The criteria that matter
Judge each option on the same five points, then match the winner to your building. Two of these rows turn on air movement, and Ventilation equipment compared is the reference for matching a fan or duct to the load before the appliance arrives.
| Criterion | Electric | Propane | Natural gas |
|---|---|---|---|
| Carbon monoxide | None produced | Produced; venting or airflow needed | Produced; venting needed |
| Installation | New 240 volt circuit and permit | Certified appliance; fitter for fixed units | Fitter, permanent line, permit |
| Output in deep cold | Steady | Falls as the tank chills | Steady |
| Portability | Cabinet units move | Cylinders move | Fixed after install |
| Best fit | Sealed, insulated shop | Detached shop with airflow | Shop with an existing gas service |
Clearances to combustibles come from the appliance label, not from habit.
Electric heat: sizing the circuit
Resistance heat turns every kilowatt hour into heat, so nothing is lost to combustion and nothing is added to the air. In February that matters.
The circuit is the constraint. A heater belongs on its own breaker, sized to the nameplate, with nothing sharing it. Provinces adopt the Canadian Electrical Code as law, and the model US rule for garage outlet requirements follows the same logic: a garage gets a dedicated branch circuit rather than a spare socket behind the freezer.
In Ontario the Electrical Safety Authority issues and inspects that permit, and unpermitted wiring tends to surface at resale.
Propane: the cylinder is the hard part
Propane throws serious heat with no service connection. It also produces carbon monoxide and water vapour. An unvented heater releases both into the room, and the vapour lands on cold steel as rust. what workshop ventilation actually does sets out why capture and filtration are separate jobs.
Storage is where propane installs go wrong. CSA B149.2 covers propane storage and handling. Cylinders belong outdoors, upright, valve closed. Refilling indoors or parking a spare tank beside the bench is the shortcut an inspector notices first.
Natural gas: cheapest run, longest lead time
Where a service already reaches the shop wall, natural gas is usually the cheapest way to heat a Canadian garage. It is also the least flexible. A licensed fitter runs the line, sets the regulator and completes the vent under CSA B149.1, and the work is inspected.
Budget for the vent and the permit alongside the heater. A separated-combustion or power-vented unit draws air from outside, so the shop can stay sealed while it burns gas.
What none of them solve
All three heat air, and none of them fix a building that loses it. A leaky door, a bare ceiling and an uninsulated slab beat any size of heater, and sealing costs less than upgrading. If the same layout problems return after every tidy-up, workshop setup mistakes keep repeating for reasons no appliance can reach.
Carbon monoxide from a running engine is the second limit. Warming a car in a closed garage is a hazard no heater design addresses. A CO alarm is a backup, not a plan.
Insurance is the third. If a heater fault burns the shop, home insurance treats tools as personal property, and many policies cap workshop contents below the cost of a full kit. Ask your broker about that limit before the install, not after.
Checks to make before you buy
- Confirm the certification mark names Canada, not only the United States.
- Measure clearance to combustibles and mark it on the floor.
- Price the circuit or gas line you need, and its permit.
- Fit a carbon monoxide alarm rated for the space.
- Ask your insurer what the workshop contents limit is.
A small checking kit of a tape measure, a voltage tester and a CO monitor answers most of this in an afternoon.
Common questions
Can I install a garage heater myself in Canada? Electrical work is permitted for homeowners in some provinces, with a permit and an inspection. Gas is different: a propane or natural gas connection requires a licensed fitter.
Are vent-free propane heaters allowed in a Canadian garage? Certification decides it. Some vent-free models are listed for the United States only, and a garage is a poor home for an appliance that dumps moisture and carbon monoxide into the room.
Do I need a carbon monoxide alarm in a garage? Ontario requires CO alarms in homes with an attached garage or a fuel-burning appliance, and other provinces have similar rules. Keep one in the garage and the sleeping-area alarms working.
Which fuel is cheapest to run? Natural gas is usually cheapest per hour of heat where a line exists. Electricity varies by province and by rate plan, so compare your own bill rather than a national average.
