Plan a detached garage around everything it may need to power, then assess the house supply and the route between the buildings. An EV charger, workshop equipment, lighting and heating can create very different demands. Installing a garage sub-panel provides local circuit space; it does not increase the home’s service capacity.
Start with a realistic equipment list
Decide whether this is mainly a parking space, a hobby workshop or a heated room used every day. Give the electrician model numbers or nameplate photos for significant equipment. A generic request for “a few plugs and an EV charger” leaves too many important assumptions open.
EV model, desired overnight charging and future second-vehicle plans.
Table saw, compressor, welder, dust collector or other equipment, including what may run together.
Heating, ventilation, garage-door openers, freezer and other permanent loads.
Workbench positions, storage, lighting and exterior receptacle needs.
Likely future changes, separated into firm plans and possibilities.
Tool nameplate ratings and operating patterns matter. The electrician must determine circuit and supply requirements; there is no universal feeder or breaker size for every detached garage.
Assess the house and garage together
Review the existing service, panel, any garage supply and the additional loads. A garage that already has lights may have only limited supply capacity. A larger sub-panel enclosure alone does not make that supply larger.
BC Hydro’s home capacity guidance explains why a professional load assessment comes before a service-upgrade decision. Where appropriate, EV load management can be considered alongside the garage’s other demands. The design must protect the relevant supply limits, including a garage feeder where applicable.
Our guide to sub-panels versus service upgrades explains the difference in plain language.
Resolve the route before landscaping or paving
Distance, access, existing underground services and the condition of any conduit can drive a large part of the work. A line on an old drawing is not proof that a usable conduit exists today. Ask who will arrange utility locating, excavation, inspections and surface restoration, and what the quote assumes about ground conditions.
Have the electrical route designed before anyone digs. Do not choose trench dimensions or installation details from a general online checklist. Property boundaries, other services, site conditions and applicable requirements must be considered.
Plan the inside before the walls are finished
Mark where the car doors open, where charging cables will hang and where tools will actually be used. Keep electrical equipment accessible rather than planning storage in front of it. Discuss separate task lighting, exterior lighting controls and convenient switching at the doors.
If future wiring pathways or communications cabling would be useful, discuss them now. An empty pathway may reduce disruption later, but does not reserve electrical capacity or guarantee that every future cable will fit.
Compare the full project cost
A useful quote separates electrical equipment and wiring from excavation, permits, wall repairs and landscaping. Ask whether the proposed supply serves the equipment you intend to use together, and whether future EV charging has been assessed or is simply an allowance for a later review.
See our garage and workshop electrical service for the information that helps define the scope. For new regulated wiring, agree on permit responsibilities before work starts. Technical Safety BC’s permit guidance also identifies municipalities that handle their own electrical permits. Building or land-use approvals are separate questions for the local municipality.
Homeowner questions
Can the garage run from my existing house service?
Often that is the starting option to assess, but suitability depends on the calculated loads, existing equipment and supply route. A detached building does not automatically need its own utility service.
Should I install the largest garage panel I can afford?
Choose the distribution equipment and feeder as a coordinated design. Extra circuit spaces can be useful, but oversizing one component without a plan does not solve capacity limits elsewhere.
Can I charge an EV while using workshop tools?
That requirement should be stated at the quoting stage. The assessment may support it directly, require managed charging or lead to a different supply design.
What if the garage might become a suite?
Tell the electrician and municipality before committing to the garage design. A future dwelling involves additional approvals and electrical requirements; garage wiring is not automatic suite readiness.
Plan your garage before work starts
For a detached garage in North Delta or the Lower Mainland, call (604) 358-5549 and speak directly with a Hundel Electric electrician. You can also text a site sketch, panel exterior photos, the approximate route and equipment details so we can review the next step.