Subpanels

Subpanel installation in Edmonton for garages, basement suites, shops and additions: feeder sizing, load checks, permits and inspection by licensed electricians.

What a subpanel is

A subpanel is a second, smaller panel fed from your main panel. It does not add capacity to your service, but it adds space for circuits, closer to where they are needed. Instead of running a dozen long circuits from the basement to a garage, you run one feeder and put the breakers out there.

Subpanels are common in garages and shops, basement suites, additions, large kitchens, and in commercial spaces where each area needs its own panel.

When a subpanel is the right answer

A subpanel makes sense when your service has enough capacity but your main panel has run out of space, or when you want circuits grouped in a separate area. It is not a fix for a service that is already at its limit.

We check this with a load calculation before recommending a subpanel. If the numbers do not work, a service upgrade may be needed instead or as well.

Getting the details right

Subpanels look simple, but there are a few details that matter for safety:

• The feeder and its breaker must be sized for the load and the subpanel rating.
• Neutral and ground must be kept separate at the subpanel; they are only bonded at the main service.
• A detached garage or shop needs its own grounding electrode and a means of disconnect.
• Feeders running underground or through unheated spaces need the right cable or conduit for the location.
• The subpanel needs proper working clearance in front of it.

Basement suites and garages

In a legal secondary suite, the suite occupant may need access to the breakers that serve their unit, and other requirements can apply depending on how the suite is set up. We check the requirements for your suite with the permit authority.

For garages and shops, see garage and workshop wiring. We usually recommend a subpanel with more spaces than you need today, so adding a welder, heater or EV charger later is easy.

Cost depends on the subpanel size, feeder length and routing, whether trenching is needed, the number of new circuits and whether the main panel needs changes to make room for the feeder breaker.

One more tip: put the subpanel where it is easy to reach. A garage subpanel behind a workbench or a suite subpanel inside a locked storage room is a nuisance the first time a breaker trips.

Commercial subpanels

In commercial buildings, subpanels are used to give each tenant or area its own set of breakers, to put circuits close to equipment, and to separate lighting, receptacle and mechanical loads. During a tenant improvement, adding a subpanel for a new kitchen, server room or production area keeps long home runs to a minimum and makes future changes easier.

We size commercial subpanels for the load and the number of circuits, label them clearly, and update the building's panel schedules so the next person knows exactly what each panel feeds.

Questions we hear