How to Snake Wires Through an Exterior Brick Wall

Adding an outdoor outlet, a light fixture, or a security camera to a brick-fronted Toronto or GTA home runs into a specific problem fast: brick does not fish like drywall. There is no cavity to snake a fish tape through the way there is inside a stud wall. This guide covers the real options for getting cable to an exterior brick location, and why most of them route around the brick rather than through it.

How to snake wires through an exterior brick wall

In most Toronto and GTA homes, exterior brick is a veneer — a single-width decorative layer with an air gap behind it, sitting in front of the actual wood-framed structural wall. That means cable typically does not run through the brick at all: it runs inside the stud wall behind the brick, fished the same way as any interior wall, and reaches the exterior fixture through a single drilled penetration at the fixture location. True solid masonry walls (rare in newer construction, more common in older heritage buildings) require a different approach: surface-mounted conduit, or a carefully drilled and sealed through-penetration at one specific point rather than any kind of fishing.

Step 1: figure out which wall type you actually have

• Brick veneer (most common in GTA construction): a single wythe of brick with an air gap, tied to the wood-framed wall behind it. The framed wall is where the cable actually runs; brick is just the exterior finish.
• Solid masonry (older heritage homes, some commercial-style construction): brick is structural, often multiple wythes thick with no separate framed wall behind it. Cable cannot be fished through this — it has to run on the surface or through a single drilled penetration.

An easy way to tell: check window and door openings for the wall’s total thickness, or look in a basement or attic where the wall’s cross-section may be visible. When in doubt, a licensed contractor can confirm quickly.

The veneer wall approach (most Ontario homes)

1. Identify the interior stud bay behind the planned exterior fixture location.
2. Fish cable through that stud bay from an accessible point — basement, attic, or an interior wall opening — the same technique used for any interior run.
3. Drill a single penetration through the sheathing and brick veneer at the exact fixture location, sized to the conduit or fixture whip passing through.
4. Install a weatherproof fixture box on the exterior brick face, sealed against the penetration with appropriate exterior sealant.
5. Terminate the cable inside the weatherproof box, connecting to the fixture.

This is functionally the same technique as how to run electrical wire through finished walls, with the brick veneer simply being the final penetration point rather than the whole run.

The solid masonry approach

• Surface-mounted conduit is the standard solution: rigid PVC or metal conduit run along the exterior brick face, secured with masonry anchors, carrying the cable to the fixture location. Visible but fully code-compliant and weatherproof when properly installed.
• A single core-drilled penetration through the solid masonry at one point, feeding from an interior location, when the fixture needs to appear to originate from inside rather than a visible exterior conduit run.
• Masonry-rated fasteners and sealant throughout — standard drywall anchors and caulk are not rated for exterior masonry exposure over Ontario winters.

Weatherproofing details that actually matter

• Every exterior penetration needs to be sealed against water intrusion, both at the brick face and, for a veneer wall, at the sheathing behind it — a single un-sealed point can let water track into the wall cavity over years.
• The fixture box itself must be rated for the location — weatherproof (in-use) covers for anything exposed to rain or snow.
• GFCI protection is required for any exterior receptacle under the Ontario Electrical Safety Code.
• A drip loop in any exposed cable run prevents water from tracking along the cable directly into the fixture box.

Why this is licensed contractor work

• Drilling into brick veneer risks cracking the brick or damaging the tie system holding it to the structure if done without the right masonry bit and technique.
• Any new exterior circuit is an alteration requiring an ESA notification, regardless of the wall type.
• Correctly identifying veneer vs solid masonry, and sizing the penetration and sealing appropriately, is exactly the kind of judgment call that separates a durable installation from one that leaks in three years.

Expert tip from our ESA-licensed electricians

The exterior brick penetrations we get called to fix in the GTA are almost always failures of sealing, not electrical failures — water tracked in around a poorly caulked penetration point, froze and thawed over a few Ontario winters, and eventually found its way into the wall cavity or the fixture box itself. The electrical connection was fine; the weatherproofing was not. If you are having any exterior fixture installed on brick, ask specifically how the penetration will be sealed, not just how the wire will get there — that is the detail that determines whether the install lasts one winter or twenty.

Frequently Asked Questions

Can I fish cable directly through solid brick?

No. Solid masonry has no cavity to fish through — use surface conduit or a single drilled and sealed penetration instead.

How do I know if my brick is veneer or solid?

Check wall thickness at a window or door opening, or have a licensed contractor confirm during the site visit.

Does an exterior outlet on brick need GFCI?

Yes, all exterior receptacles require GFCI protection under current Ontario code.

Is surface conduit ugly on a brick house?

Paintable conduit matched to the mortar or brick colour can blend reasonably well, though it remains visible compared to a concealed run.

Do I need a permit for an exterior outlet on brick?

Yes. Any new exterior circuit requires an ESA notification and inspection.

Related reading from ezsmart.ca

• How to Run Electrical Wire Through Finished Walls
• How to Trace a Wire Through a Wall Without Tearing It Open
• Are Outdoor Outlets Required to Be GFCI Protected?
• Can Water Get Inside an Outdoor Breaker Box?
• How to Seal Conduit Entering the Breaker Box

Contact us

Need an exterior fixture wired through a Toronto or GTA brick wall? Call ezsmart at 416-838-9006 or use our contact page. An ESA-licensed electrician will route and seal it properly.