Compiling answers to the most common interlock driveway questions we see on this forum.
Q: How long does interlock last?
A properly installed interlock driveway lasts 20–30+ years. The pavers themselves rarely fail — it’s usually the base preparation that determines longevity. Poor base = frost heave in 2–3 winters.
Q: What base thickness is required in Toronto?
Minimum 6" compacted Granular A sub-base for pedestrian areas; 8–10" for driveways with vehicle traffic. Some contractors cut corners here — ask specifically what depth they’re excavating and compacting to.
Q: Can I repair heaved interlock myself?
Yes, relatively easily. Remove the affected stones, add or remove base material as needed to level, re-lay stones, compact, and re-sand joints with polymeric sand. This is the main advantage of interlock over concrete.
Q: What’s polymeric sand and why does it matter?
Polymeric sand contains binders that, when activated by water and compacted, harden slightly. It resists ant intrusion, erosion, and joint weed growth better than regular sand. Always use polymeric sand — don’t let a contractor cut costs here.
Q: Does interlock need sealing?
Optional. Sealing enhances colour and provides some stain protection. It doesn’t affect structural performance. Many installers recommend sealing 6 months after installation once the polymeric sand has fully set.
Q: How do I find a reliable interlock contractor?
Read reviews from Toronto homeowners who’ve had interlock installed — this forum is the best source. Verify WSIB and insurance, ask for a project portfolio with photos, and check if they’re willing to excavate and prepare the base properly.
What other interlock questions do you have?