How do i run new electrical to a detached garage 80 feet from my house in Rothesay — underground or overhead?

Running power to a detached garage in Rothesay is absolutely doable, and you have two legitimate options — underground conduit or overhead service entrance cable — but this is licensed-contractor territory in New Brunswick, not a DIY project.

Before getting into the technical comparison, the regulatory picture: all electrical work in NB must be performed by a licensed electrical contractor (licence issued by NB Dept. of Justice and Public Safety — Technical Inspection Services). Your contractor must obtain an electrical wiring permit from NB Power (1-800-615-0522) before any work begins, and TIS will conduct a final inspection once the wiring is complete. Working without that permit triggers a special inspection fee on top of the permit cost — and your home insurance could deny a claim if unpermitted electrical work is involved.

For your building permit, since Rothesay is an incorporated town, you'd contact the Town of Rothesay Planning Department at (506) 848-6600. A detached garage with a new electrical subpanel will almost certainly require a permit.

---

Underground vs. Overhead — The Real Comparison

Underground is the preferred method for most Rothesay homeowners and here's why: it's cleaner, no overhead lines crossing your yard, no tree-trimming concerns, and it won't be damaged by ice storms (NB gets hit hard). The tradeoff is digging.

For underground runs, you have two approaches:

• Direct-burial cable (USE-2 or similar) — buried at minimum 600mm (24") depth under general areas, 450mm under concrete slabs


• Conduit (PVC or rigid metal) with THWN wire inside — more expensive upfront but allows future wire upgrades without re-digging

At 80 feet, voltage drop becomes a real consideration. Most electricians will size up the wire — commonly running 6 AWG copper or even 4 AWG for a 60-amp subpanel, especially if you're planning to run a welder, compressor, EV charger, or heat in that garage. Discuss your anticipated load with your electrician before they size the wire and breaker.

NB's frost line is 4+ feet (1.2m+) — but electrical burial depth requirements under the NBC and Canadian Electrical Code are shallower than frost depth, so the trench doesn't need to go that deep. Your electrician will know the exact requirements for your installation type.

Overhead service entrance cable (SER or triplex) is faster and cheaper to install — no trenching, less labour. The limitations: you need adequate clearance (minimum 3m/10 feet above ground in general areas, higher over driveways and public spaces per the Canadian Electrical Code), and any trees between your house and garage will need to be clear of the span. At 80 feet, you may also need a mid-span support pole depending on sag calculations.

Cost ranges for Rothesay/Greater Saint John area:

• Underground with conduit and 60A subpanel: $3,500–$6,500
• Underground direct-burial with 60A subpanel: $2,500–$4,500
• Overhead triplex with 60A subpanel: $1,800–$3,500

These ranges include the permit, trenching or overhead hardware, wire, subpanel, and breakers — but not any interior garage wiring beyond the panel itself.

One thing worth thinking about now: if there's any chance you'll want an EV charger, a welder, or electric heat in that garage in the next decade, tell your electrician upfront. Sizing up to a 100-amp subpanel adds relatively little cost at this stage but saves a complete redo later. The conduit approach is especially smart for this reason — pull heavier wire in the future without touching the ground again.

Find a licensed electrical contractor through the New Brunswick Construction Network directory, and make sure they're registered with WorkSafeNB before work begins — you can verify at worksafenb.ca or call 1-800-999-9775.