A century brick home in Dundas came to us after the homeowners noticed a crack spreading across the basement wall over the course of a winter. This is a walkthrough of how we identified what kind of crack it actually was, why we recommended wall reinforcement over a costlier fix, and what the finished result looked like.
The Problem
The homeowners first noticed a thin vertical line in the fall. By late winter it had become a clearly horizontal crack running most of the length of one basement wall, with the wall itself showing a slight inward bow when checked with a straightedge. No water was entering yet, but the movement was visibly progressing.
The distinction that mattered: a horizontal crack means lateral soil pressure has overcome the wall's bending resistance - a different problem than a vertical shrinkage crack, and one that needed a prompt structural assessment rather than a wait-and-see approach.
The Diagnostic Assessment
Our structural assessment confirmed the crack was horizontal and structural, not cosmetic, and measured the wall's bow at just under half an inch of inward deflection over its height. Critically, the footing itself showed no signs of active settlement - the problem was lateral soil pressure against the wall, consistent with Hamilton's clay-heavy soil and a winter of freeze-thaw cycling, not a sinking foundation.
Why We Recommended Wall Reinforcement
Since the footing was stable and the issue was lateral pressure rather than settlement, full underpinning would have been unnecessary cost and disruption for a problem reinforcement could solve directly.
The Scope
Carbon fibre reinforcement straps installed vertically across the affected wall section, anchored top and bottom, to arrest further inward movement and stabilize the wall permanently.
The Work
The affected wall section was cleaned and prepped, and carbon fibre straps were epoxy-bonded vertically across the crack at regular intervals, anchored into the floor slab below and the floor joists above. No excavation was required since the fix addressed the wall directly rather than the footing. The crack itself was also sealed with polyurethane injection as part of the same visit, restoring the wall's waterproofing along with its structural integrity.
The Result
- Wall movement fully arrested - no further deflection measured a full year after completion
- Crack sealed and waterproofed as part of the same scope, no separate visit needed
- No excavation, no disruption to the yard or landscaping
- 5-year structural warranty on the completed reinforcement
This project is a good example of why diagnosis has to identify the actual mechanism before recommending a fix - a horizontal crack can mean very different things depending on whether the footing below it is moving, and getting that distinction right kept this homeowner from paying for underpinning they didn't need. For method and pricing details, see our foundation repair service page.
Frequently Asked Questions
The crack ran horizontal across the block wall rather than vertical - a horizontal orientation means lateral soil pressure has overcome the wall's bending resistance, which is the defining sign of a structural crack rather than a cosmetic shrinkage crack.
The wall had bowed but the footing itself was not settling - the foundation wasn't sinking, the wall was just under lateral pressure. Carbon fibre reinforcement stabilizes a wall against that pressure without the cost and scope of underpinning, which addresses a sinking footing instead.
No, and that's not the goal. Carbon fibre reinforcement stops further movement and stabilizes the wall at its current position - it doesn't push a bowed wall back to perfectly plumb, which would require a different and far more invasive repair.