How deep should a paver base be?
4 to 6 in of compacted crushed stone for a patio, 8 to 12 in for a driveway.
Then exactly 1 in of bedding sand on top — screeded, not compacted, and never deeper. That last number is where most paver patios fail.
Base depth by use
| Use | Compacted base | Total excavation | Gravel for 200 sq ft | Tons |
|---|---|---|---|---|
| Walkway or patio, good soil | 4 in | 5 in | 2.47 | 3.5 |
| Patio, clay or soft soil | 6 in | 7 in | 3.7 | 5.2 |
| Driveway, good soil | 8 in | 9 in | 4.94 | 6.9 |
| Driveway, clay or soft soil | 12 in | 13 in | 7.41 | 10.4 |
Excavation is base plus the 1 in of sand plus the thickness of the paver itself — a 60 mm paver adds another 2 3/8 in, so a patio on a 6 in base means digging about 9 1/2 in below your finished height.
Why an inch of sand and not three
Sand is easy to spread and gravel is work, so the temptation is to skip base depth and bed the pavers on a thick layer of sand instead. It looks identical the day it is finished.
The difference is that crushed stone with fines compacts into something that behaves like soft rock, and sand does not. Sand is a fluid under load — it migrates sideways out from under whatever is being walked on. Three inches of it gives every footstep three inches of material to displace, and within two seasons the patio has ruts along the route people actually walk, usually to the door.
One inch, screeded flat and never compacted before laying, is the whole allowance. Its job is to let each paver seat itself, not to level the base.
Common questions
- What size crushed stone for a paver base?
- 3/4 in minus — crushed, angular, with the fines still in it. Sold as Class 5, road base, or 3/4 minus depending on the region. Clean stone with the fines washed out will not lock together and stays loose forever.
- How deep for a walkway?
- 4 in of compacted base is enough in good soil, because a walkway only ever carries people. Soft or clay soil still wants 6.
- How deep for a driveway?
- 8 in minimum in good soil, 12 in clay. A car is thousands of pounds concentrated on four small contact patches, and it turns, which grinds sideways as well as pressing down.
- Do I compact in layers?
- Yes — 3 to 4 in at a time, each one compacted before the next goes down. A plate compactor only densifies the top few inches, so a single 8 in lift is a compacted crust over loose stone, which settles unevenly later.
- Does it need to slope?
- About 1/4 in per foot, away from any building. Pavers are not waterproof and the base must drain; the slope is set in the base and carried through the sand, not corrected at the end.
- How much wider than the patio should the base be?
- Extend it 6 to 12 in past every edge. The outermost pavers are the ones most likely to shift, and they need base under them and edge restraint against them.
Related answers
Or size a specific patio with the paver guide.