🧱 Interlock, Flagstone & Patios: what it costs in the GTA (2026)

Pavers don't wear out; bases do. Under every wavy, sunken GTA driveway is a base that was too shallow, poorly compacted, or built on unprepared clay. Do it right and you excavate 8–12 inches, lay geotextile so the granular doesn't sink into the clay, then compact granular in 4-inch lifts before a paver ever shows up. That's most of the labour and most of the cost, and it's buried where you can't see it. Which is exactly why cheap quotes skip it.

Water gets under pavers, freezes, expands about 9%, and lifts whatever sits above it. Come thaw, things settle unevenly. Repeat forty times a winter. A proper base drains so there's less water to freeze, and polymeric sand in the joints hardens to keep new water from getting in. That's why re-sanding joints every 2–3 years is the one maintenance job interlock actually asks of you.

Flagstone looks incredible and no two patios are alike, but it costs more, and dry-laid flagstone wants a fussier base and periodic re-levelling. Concrete pavers are engineered to be uniform, stronger than poured concrete per square foot, and any single damaged unit lifts out and swaps. Driveways: pavers, almost always. Garden paths and showpiece patios: stone earns its price. We install both and we'll tell you where each belongs.

If your interlock is wavy but the pavers themselves are sound, you don't need a new patio. We lift the affected field, rebuild and compact the base under it, and relay the same stones with fresh joint sand. It runs a fraction of full replacement, usually $2,000–$6,000, and the result is dead flat. Contractors who only sell full teardowns don't love this option. It's still the right call for a lot of homes.