Should my NB shed have its own subpanel?

Whether your NB shed needs its own subpanel depends on how much power you plan to use — but for most sheds with more than basic lighting, a subpanel is the right move.

If you're running just a couple of lights and maybe one outlet, a single 15A or 20A circuit run from your main panel might be all you need. But if you're planning a workshop with power tools, a welder, an air compressor, or even just multiple circuits for convenience, a subpanel in the shed makes far more sense than running multiple individual circuits from your house.

Why a subpanel makes sense for most sheds

Running multiple circuits from your main panel to a detached shed means multiple underground runs — each one requiring its own trench, conduit, and wire. A single larger feed to a subpanel (typically a 60A or 100A feed) is usually cheaper and cleaner than three or four separate circuit runs. It also gives you room to grow. A small 6-circuit subpanel in the shed lets you add circuits later without touching your main panel or digging new trenches.

There's also a safety and code reason: the Canadian Electrical Code (as adopted in New Brunswick) requires a disconnect means at a detached structure. A subpanel with a main breaker satisfies this requirement — meaning you can shut off power to the entire shed from inside the shed, which matters if there's ever a fault or emergency.

NB-specific considerations

New Brunswick's climate is hard on outdoor electrical. Underground runs to your shed need to account for frost depth — in NB, that can reach 1.2m to 1.5m depending on your location. Your electrician will typically run the feed in conduit or use direct-burial cable rated for the application. For coastal areas near Saint John or Shediac, any exterior components should be rated for salt-air exposure.

This work requires a TSANB permit — running a new circuit or subpanel to a detached structure is not a DIY project in New Brunswick. Your licensed electrician will pull the permit, complete the work, and a TSANB inspector will sign off before the job is done. Unpermitted shed wiring is a real problem when it comes to home insurance claims or selling your property.

Typical costs in New Brunswick for a shed subpanel installation run $800 to $1,500 for the subpanel itself, plus the cost of the underground feed run (which varies significantly based on distance from your house to the shed). Budget $1,500 to $3,000 total for most residential shed setups — more if your main panel needs capacity added first.

If you're not sure what your shed needs, a licensed electrician can assess your main panel capacity and your planned shed usage to recommend the right setup. New Brunswick Electrical can match you with a local electrician for a free estimate — it's worth getting a proper assessment before you start digging.