Why Paver Failures Are Almost Always Base Failures
When a paver surface shifts, dips, or grows weeds through spreading joints, the pavers didn't fail — the installation did. A paver system is only as good as the layers underneath it, and those layers are where a cut-rate crew saves a few hundred dollars that turns into thousands of dollars of settling within two or three years. Built to the Interlocking Concrete Pavement Institute (ICPI) standard, the way Shaun builds it, a paver surface is an engineered assembly.
It starts with excavation to the right depth and a compacted aggregate base — typically four inches of Class II road base for pedestrian areas and deeper for driveways — compacted to at least 95% standard Proctor density (ASTM D698), the vehicular version compacted harder still. A shallow or loosely compacted base is the number-one cause of paver failure in San Diego, full stop. On top of that goes a screeded bedding layer of coarse concrete sand — ASTM C33, not bagged play sand or beach sand, because evenly graded sand doesn't lock together and won't hold the pavers in place. The pavers are then laid in pattern, with herringbone used for driveways because its interlocking geometry resists the lateral forces of vehicle traffic far better than a running bond.
The detail that separates a lasting installation from a spreading one is the edge restraint. Set around the perimeter and spiked into the compacted base, it's what stops the whole field of pavers from creeping outward and opening joints over time — the single most-skipped component on cheap jobs. Finally the joints are filled and locked, typically with polymeric sand that hardens to resist weeds, ants and washout. None of this shows in the finished surface, which is exactly why it's where discipline matters — and where a masonry contractor who builds structural bases every week has the advantage over a crew that treats the base as an afterthought.