How much does it cost to add a sub-panel in my Calgary garage?

Adding a sub-panel to a Calgary garage typically costs between $1,000 and $2,200, depending on the amperage, the distance from your main panel to the garage, and whether the garage is attached or detached. This is one of the most practical electrical upgrades for homeowners who want dedicated power for a workshop, EV charger, heated garage, or additional circuits without overloading existing branch circuits.

For an attached garage, where the sub-panel is mounted on the wall shared with the house, a 60-amp sub-panel runs about $1,000 to $1,500 installed. The electrician runs a feeder cable (typically 6/3 NMD90 copper for 60 amps) from a dedicated breaker in your main panel to the new sub-panel, installs the sub-panel box, adds individual breakers for your garage circuits, and pulls the required City of Calgary electrical permit. A 100-amp sub-panel for a more demanding setup costs $1,400 to $2,200 and uses heavier feeder cable (3/3 or 2/3 copper).

For a detached garage, costs increase to $1,500 to $2,800 or more because the feeder cable must be run underground in approved conduit. The Canadian Electrical Code requires underground wiring to be in rigid PVC conduit or TECK cable, buried at the depth specified by Alberta requirements — typically at least 600mm (24 inches) deep for residential circuits in conduit, though many Calgary electricians bury deeper to account for frost heave. Calgary's frost depth exceeds 1.2 metres, and while electrical conduit does not need to be below the frost line, deeper burial provides better protection against ground movement from freeze-thaw cycles and chinook-induced soil shifting. Trenching costs add $15 to $40 per linear foot depending on soil conditions and distance.

Choosing the right sub-panel size depends on what you plan to run in your garage. A 60-amp sub-panel handles basic workshop needs — overhead lighting, several outlets for power tools, a small compressor, and a garage door opener. If you want to add a Level 2 EV charger (40 to 50 amps on its own), a garage heater (15 to 30 amps for electric models), or a welder (50 amps), you need at least a 100-amp sub-panel. Many Calgary electricians will recommend going with 100 amps even if your current needs are modest, because the cost difference between a 60-amp and 100-amp sub-panel is only about $200 to $400 in equipment, and running a heavier feeder cable now avoids tearing up the conduit run later.

One critical consideration: your main panel must have enough spare capacity to feed the sub-panel. If your main panel is a 100-amp unit already running near capacity, adding a 60 or 100-amp sub-panel may require upgrading the main panel to 200 amps first — adding $1,800 to $3,500 to the total project cost. A licensed electrician will perform a load calculation to determine whether your main panel can support the additional load.

The sub-panel in the garage needs its own grounding electrode (ground rod) if the garage is a separate structure, as required by the Canadian Electrical Code. All garage outlets must be GFCI-protected, and the sub-panel itself must be installed at the correct height with proper clearances. The City of Calgary electrical permit is required, and a Safety Codes Officer will inspect the completed work. Browse electricians in the Calgary Construction Network directory to find qualified professionals for your garage sub-panel project.