My garage floor is uneven and cracked, what are my options for leveling and resurfacing?

Uneven and cracked garage floors are extremely common in Ottawa due to our freeze-thaw cycles, clay-heavy soils, and the general settling that happens over decades. Your repair options range from about $500 for basic patching up to $8,000 or more for a complete resurfacing, depending on the severity of the damage and what you plan to do with the space.

For minor cracks under a quarter inch wide, hydraulic cement or polyurethane crack filler handles the job for under $100 in materials. These are straightforward repairs that most homeowners can do themselves. Clean out the crack, apply the filler, and let it cure. This is cosmetic and functional for a standard parking garage but will not give you a smooth surface for a workshop or living space conversion.

Self-levelling concrete overlay is the most popular solution when the floor has moderate unevenness, meaning dips or slopes of up to about an inch across the slab. A professional pours the self-levelling compound over the existing floor, and it flows to create a flat, smooth surface. In Ottawa, this costs $3 to $6 per square foot installed, so a two-car garage runs $1,800 to $3,600. The existing slab needs to be structurally sound for this to work. If the concrete is heaving or has large sections that move independently, levelling compound alone will not solve the underlying problem.

If the slab has significant structural damage with heaving sections, wide cracks, or areas that have sunk more than an inch, you may need mudjacking or polyurethane foam injection to stabilize the slab before resurfacing. Mudjacking pumps a cement slurry under the slab to lift sunken sections and costs $500 to $1,500 for a garage. Polyurethane foam injection is more precise and lighter weight, running $1,000 to $2,500. Both are far cheaper than pouring a new slab.

A complete slab replacement is the last resort and costs $6,000 to $12,000 for a two-car garage in Ottawa. This involves demolishing the existing concrete, re-grading the base, and pouring new concrete with proper reinforcement. It is the right choice when the existing slab is beyond repair, but most garages do not need this level of intervention.

Once the floor is level and sound, you have several finishing options. Epoxy coating is popular for workshops and general use, running $1,500 to $3,500 professionally applied. It creates a durable, chemical-resistant surface that is easy to clean. Polished concrete is an attractive option for living space conversions at $3 to $8 per square foot. For a workshop, many people simply seal the levelled concrete with a penetrating sealer for $200 to $500 and call it done.

In Ottawa, the best time for concrete floor work is late spring through early fall when temperatures stay above 10 Celsius for proper curing. Winter pours are possible with heated enclosures but add cost and complexity.

---

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

• 613Bins
• RenoMotion Inc.
• Diamond renovations
• GDS - Garage Doors & Openers Ottawa
• The Next Reno