Should I overlay or tear out a damaged Ottawa driveway?

The decision between overlay and tear-out depends entirely on the condition of your existing base and the extent of surface damage. If your driveway has widespread cracking, settling, or drainage issues, overlay is a temporary fix that will fail within 1-2 Ottawa winters. If the base is stable with only surface wear, overlay can be cost-effective.

Overlay works only when the existing base is solid. Minor surface cracking (hairline cracks less than 5mm wide), oxidation, and wear are good candidates for overlay. The existing asphalt must be structurally sound with no major settling, heaving, or alligator cracking. Before overlay, all cracks wider than 5mm should be filled with hot-pour crack sealer, and any loose material must be removed. A 50mm overlay of HL3 surface course asphalt typically costs $2,500 to $5,500 for an average Ottawa driveway and adds 8-12 years of life when done properly.

Tear-out and replacement is necessary when the base has failed. Signs of base failure include widespread alligator cracking (interconnected cracks forming a pattern like reptile skin), areas that flex or feel spongy underfoot, standing water that doesn't drain, sections that have settled more than 25mm, or extensive edge cracking where the driveway meets grass or concrete. These problems indicate the granular base beneath the asphalt has shifted, settled, or been compromised by water infiltration. Overlaying these conditions locks the problems beneath a thin new surface — every crack and movement will reflect through the overlay within one freeze-thaw season.

Ottawa's extreme climate makes overlay particularly risky on marginal driveways. Our 50+ annual freeze-thaw cycles and deep frost penetration (1.2-1.5 metres) stress any underlying weaknesses. Water that penetrates overlay joints or reflects cracks freezes and expands, accelerating failure. Many Ottawa driveways built in the 1980s and 1990s have minimal base depth by today's standards — overlaying these without addressing base deficiencies is throwing good money after bad.

Proper evaluation requires examining the entire driveway system. Walk your driveway after heavy rain to identify drainage problems. Look for areas where water pools or runs toward your foundation. Check for settlement by laying a straight board across suspected low spots. Probe soft areas with a screwdriver — if it penetrates easily, the base has likely failed. Pay special attention to the driveway edges where water infiltration typically begins.

Full replacement costs $5,000 to $12,000 but addresses all underlying issues. This includes removal of existing asphalt, evaluation and repair of the granular base (adding material if needed), proper compaction, and installation of new asphalt in two lifts (binder and surface course). While expensive upfront, a properly rebuilt driveway lasts 20-25 years with regular sealcoating versus 8-12 years for overlay on a good base or 1-3 years for overlay on a failed base.

When in doubt, get a professional assessment. An experienced paving contractor can evaluate your base condition, identify drainage issues, and recommend the most cost-effective approach. Getting multiple opinions helps ensure you're not being oversold on unnecessary work or undersold on critical base repairs.

Need help finding a driveway contractor for a professional assessment? Ottawa Driveways can match you with local paving professionals who understand Ottawa's unique soil and climate challenges.