A paver patio is only as good as what sits under it. The pavers are just the surface. The base does the structural work, spreading load and draining water so the surface stays flat and level for years rather than heaving and settling after the first winter.
The layers, bottom to top
- Compacted subgrade: the native soil, excavated to depth and compacted flat.
- Gravel base: crusher run or road base, laid and compacted in layers.
- Bedding sand: a thin, screeded layer the pavers sit in.
- Pavers: the surface, with joints filled by jointing sand.
- Edge restraints: hold the whole field from spreading sideways.
Typical depths
| Use | Gravel base | Bedding sand |
|---|---|---|
| Patio, walkway | 4 in (10 cm) | 1 in (2.5 cm) |
| Driveway | 6 to 8 in | 1 in (2.5 cm) |
| Poor or clay soil | Add 2 in or more | 1 in (2.5 cm) |
Estimating the materials
Work out the patio area, then calculate the gravel and sand as volumes at their depths. For a 12 by 16 patio at 192 square feet, a 4 inch gravel base is about 2.4 cubic yards, and a 1 inch sand bedding layer is about 0.6 cubic yards. The paver calculator returns the paver count plus both base volumes in one step, so you can order everything together.
Excavation depth
Dig deep enough for all the layers plus the paver thickness, so the finished surface sits where you want it. For a patio that is roughly the gravel base, plus the sand, plus the paver, often around 6 to 7 inches of total excavation. Check the finished height against any adjoining door threshold or path.
Why compaction matters
An uncompacted base will settle unevenly under use, and no amount of careful paver laying fixes that. Compact the subgrade, then compact the gravel in layers of a few inches at a time. A plate compactor is the right tool, and many people rent one for a weekend. Do not compact the bedding sand itself, screed it level and lay straight onto it.
Drainage and slope
Set a slight slope, around one eighth of an inch per foot, away from the house so water runs off the surface. A flat patio holds puddles and ices over in winter, and water sitting on the surface eventually works its way into the joints and base.