Our driveway has sunk and water pools in low spots after a few years — is re-grading worth the cost?

Driveway settling is extremely common in Ottawa, and those low spots that collect water are more than just an annoyance — they accelerate deterioration of your driveway surface and can cause foundation issues if the pooling is near your house.

Why Ottawa Driveways Settle

Our climate is uniquely hard on driveway subgrades. The annual freeze-thaw cycle — with frost penetrating over a metre deep during sustained -25°C to -30°C stretches — heaves the soil upward in winter and lets it compact unevenly when it thaws. Repeat this 80-100 times per winter (Ottawa averages about 90 freeze-thaw transitions annually) and you get differential settlement. Areas with Leda clay are especially vulnerable; this marine clay shrinks when dry and expands when wet, creating ongoing movement that no surface material can withstand without proper base preparation.

Re-Grading Options and Costs

Asphalt overlay (top-up) is the most common approach for asphalt driveways with moderate settling. A layer of new hot-mix asphalt is applied to fill low spots and restore proper drainage slope. Cost: $3 to $6 per square foot, so a typical Ottawa driveway (400-600 sq ft) runs $1,200 to $3,600. This works well if the settling is under 5 cm and the base is still reasonably intact.

Full removal and re-grading is necessary when settling exceeds 5-8 cm or when the base layer has been compromised by water infiltration. The old surface is removed, the base is re-compacted and corrected, and new asphalt or concrete is laid. Cost: $8,000 to $18,000 for a full driveway in Ottawa, depending on size and material.

Mudjacking or foam levelling works for concrete driveways. Small holes are drilled and material is injected beneath the slab to raise it to the correct grade. Cost: $1,000 to $3,500, roughly one-third the cost of full replacement. However, if the concrete is badly cracked, levelling may not be worthwhile.

Is It Worth It?

Absolutely, in most cases. Standing water on asphalt penetrates through cracks, saturates the base, then freezes and creates potholes — the classic Ottawa pothole cycle. A $2,000 re-grading job now can prevent a $12,000 full replacement in three to four years. If water is pooling near your foundation, the stakes are even higher — basement waterproofing in Ottawa runs $8,000 to $20,000, making driveway grading look like a bargain.

Timing

The best time for re-grading in Ottawa is May through October when asphalt plants are running and soil conditions are stable. Avoid late-season work (November) as cold asphalt doesn't compact properly.

Reach out through Ottawa Driveways to get assessments from local contractors who understand Ottawa soil conditions and can recommend the right approach for your situation.

---

Looking for experienced contractors? The Ottawa Construction Network connects Ottawa homeowners with qualified professionals:

• 613Bins
• RenoMotion Inc.
• JMY Renovations
• Elie The Carpet Guy Inc.
• Humble Homes - property maintenance