A hairline crack that's flush and level is cosmetic — sealing costs $150 to $300. If one side sits higher than the other and you can feel it with your foot, it's a trip hazard needing polyurethane or epoxy injection ($750 to $1,500) or, in the worst case, full slab replacement.
Almost every Woodbridge driveway, walkway, and porch slab has at least one crack in it, and most of those cracks aren't a problem at all. The one that actually matters is different in kind, not just in size: it's a slab that's moved, not just one that's cracked. Telling those two apart before you call anyone is a two-minute check, and it decides whether you're looking at a $150 afternoon or a full slab replacement.
Why Woodbridge sees more of this than a newer subdivision does
Vaughan sits on heavy clay soil through most of its established neighbourhoods, and clay behaves badly with water: it swells when it's saturated and shrinks hard when it dries out. Layer that onto a typical Ontario winter — well over 100 freeze-thaw cycles a year, not one long freeze — and you get a base underneath every slab that's constantly expanding and contracting instead of sitting still. Water that gets into an under-engineered base freezes and expands by roughly 9%, which is what actually lifts or tilts a slab; it's the same mechanism, on a smaller scale, that causes frost heave on a road.
Woodbridge's older, established lots feel this more than a subdivision poured in the last decade, for a simple reason: original concrete walkways and driveway aprons from the 1980s and 90s have gone through three or four decades of that cycle, on a base that was built to a different standard than what gets poured today. None of that means the concrete was installed badly — it means it's had more winters to work with.
The check that actually separates cosmetic from structural
A hairline crack — under about 1/8 inch wide, with both sides sitting flush and level with each other — is shrinkage cracking. Nearly all poured concrete develops it as it cures, and it's cosmetic. It doesn't get worse in any way that matters, and it's not a sign the slab is failing.
What you're actually checking for is vertical offset — one side of the crack sitting higher than the other. Ontario's own Minimum Maintenance Standards for Municipal Highways (O. Reg. 239/02) uses a specific number for this on public sidewalks: a surface discontinuity of more than 2 cm (a little under an inch) is the threshold a municipality has to act on as a trip hazard. That rule is written for public sidewalks, not your own walkway, but it's a genuinely useful benchmark to borrow — if you can catch your toe on the edge, or you can rock a flashlight beam visibly across the step between two slabs, you're past cosmetic and into "this needs a real fix," whatever the crack itself looks like.
- Flush and level, hairline width — cosmetic. Worth sealing so water doesn't get in and make it worse, not urgent beyond that.
- Offset you can feel with your foot, or a slab that rocks when you step on it — the base underneath has genuinely shifted. This is the trip-hazard category, and homeowner's insurance won't care that "it's just a walkway" if a visiting guest goes down on it.
- A crack that's noticeably wider in February than in August — still actively moving with the freeze-thaw cycle, which usually means the base hasn't stabilized yet and sealant alone won't hold.
What a real fix costs in 2026
HST (13%) applies on top of every price below. Which of these applies depends entirely on the check above, not on how the crack looks:
- Sealing a cosmetic hairline crack — a flexible concrete caulk, applied to keep water out before winter: roughly $5–$8 per linear foot, or $150–$300 as a minimum call-out if a craftsman is sealing several cracks around a driveway or patio in one visit.
- Polyurethane injection — for a crack that's still moving seasonally and needs a flexible repair rather than a rigid one: roughly $750–$1,000 per crack for a driveway or walkway-scale repair.
- Epoxy injection — for a crack where the concrete itself needs structural strength restored, not just sealing: roughly $850–$1,500 per crack. This is the pricier option because epoxy bonds rigidly rather than flexing, and it's typically the wrong call on a slab that's still actively moving — a rigid repair on a moving base just re-cracks next to itself.
- Full slab replacement — the honest answer once a slab has genuinely settled, tilted, or broken up rather than just cracked: roughly $12–$22 per square foot, including demolition, disposal, and a new pour. A typical single walkway slab (about 3 ft by 5 ft) runs in the $200–$400 range on its own; a full front walk or driveway apron scales up from there.
- Mudjacking (raising a sunken slab instead of replacing it) — worth asking about specifically, because it's a genuinely different price point when it applies: roughly $4–$9 per square foot, cheaper than a full replacement. The catch is availability — fewer GTA concrete contractors offer it compared to the U.S., where it's more common, and it only works when the slab itself is intact and just sitting low, not cracked or broken up. Ask directly whether a quote is for lifting the existing slab or pouring a new one; they're not the same job at the same price.
Permits: almost always maintenance, with two real exceptions
Repairing or replacing an existing walkway or driveway apron in its current footprint, using the same or similar material, is treated as maintenance by the City of Vaughan and doesn't trigger a building permit. Two things genuinely change that:
- Widening the driveway or altering the curb cut — this needs approval from the City of Vaughan under the Zoning By-law, a separate process from a building permit, and it takes roughly four weeks to process. If your "walkway repair" is actually turning a single-car apron into a wider one, budget the time for this step before the concrete gets poured.
- Changing drainage as part of the repair — if the new slab will shed water differently than the old one, especially toward a shared property line, that's worth raising with your craftsman before the pour, not after a neighbour notices.
A straight like-for-like repair or replacement clears both of these without any extra step. When in doubt on a specific job, Vaughan's Building Standards department (905-832-8510) will tell you directly rather than leaving it to guesswork.
What's worth fixing now vs. leaving until spring
Sealing a hairline crack is worth doing before winter regardless of urgency — it's cheap, and keeping water out of it now is what keeps it cosmetic next year instead of letting it turn into a freeze-thaw problem. A genuine trip hazard is worth fixing on its own timeline, not the season's: a slab that's actually unsafe to walk on doesn't get safer by waiting for warmer concrete-pour weather. If a full replacement is the honest answer but it's late in the fall, a temporary asphalt cold-patch or a clearly marked hazard is a reasonable stopgap until spring pour season — just don't let "we'll deal with it in spring" quietly become "we forgot about it by spring."
Quick answers
How much does it cost to seal a cosmetic concrete crack in Woodbridge?
Sealing a hairline crack with flexible concrete caulk runs $5 to $8 per linear foot, or $150 to $300 as a minimum call-out if a craftsman seals several cracks in one visit.
How do I know if a concrete crack is a trip hazard, not just cosmetic?
Check for vertical offset — one side of the crack sitting higher than the other. If you can catch your toe on it or feel a slab rock when you step on it, it's past cosmetic and needs a real fix.
How much does crack injection repair cost?
Polyurethane injection, for a crack still moving seasonally, runs $750 to $1,000 per crack. Epoxy injection, for a crack needing structural strength restored, runs $850 to $1,500 per crack.
How much does full slab replacement cost in Woodbridge?
Roughly $12 to $22 per square foot, including demolition, disposal, and a new pour. A typical single walkway slab (about 3 by 5 feet) runs $200 to $400 on its own.
Do I need a permit to repair a driveway or walkway in Vaughan?
No, repairing or replacing an existing walkway or driveway apron in its current footprint and material is treated as maintenance. A permit-level process only applies if you're widening the driveway, altering the curb cut, or changing how water drains off the new slab.
Related reading
- More home repair guides for Woodbridge
- Small Foundation Crack Sealing Cost in Woodbridge: Cosmetic vs. Structural
- Fence Board or Panel Repair vs. Full Replacement in Woodbridge
- Deck Board Replacement and Small Deck Repairs in Woodbridge
- How Do Building Permits Actually Work in York Region?
- Pre-Listing Small Repair Punch List for a Woodbridge Home
- Mailbox, Railing & Small Exterior Fixture Repair Cost in Woodbridge
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