How the paver base calculator works
Each layer's job
Geotextile separates soil from stone (stops migration). Compacted crusher run carries the load — 4" for walks, 8–10" for driveways, always in compacted 2" lifts. One inch of concrete sand screeds the level plane; it is a leveling bed, not structure, which is why it never gets compacted and never exceeds an inch. Pavers lock the surface; joint sand locks the pavers.
The one-inch sand rule
The classic DIY error is 2–3 inches of sand "to make leveling easier" — loose sand settles unevenly under load and the patio develops its personality by year two. One inch, screeded flat over compacted base, then pavers pressed in without disturbing the bed. The screed rails (two 1" pipes) are the whole technique.
Excavation arithmetic
Dig depth = base + 1" sand + paver thickness (~2 3/8" for standard) — call it 7–8" for a patio, 12"+ for a driveway. The spoil pile is real: a 16×12 patio excavates ~1.7 cubic yards that need a trailer and a destination. Utilities get located (811 call) before any digging, universally and without exception.