Everything under a paver patio
A paver patio is more than pavers. It sits on a compacted gravel base, a thin bed of sand and a border that holds everything in place. This calculator counts the pavers with a waste factor for your pattern, and works out the gravel and sand in cubic yards and tons, the edging length and the total cost.
The formulas
- Pavers per square foot = 144 ÷ (paver length × paver width), in inches.
- Pavers = area × pavers per square foot × (1 + waste).
- Base gravel = area × base depth ÷ 12 ÷ 27, plus 20% for compaction. Crushed stone weighs about 1.4 tons per cubic yard.
- Bedding sand = area × sand depth ÷ 12 ÷ 27, at about 1.35 tons per cubic yard.
- Edging = perimeter of the area.
Worked example: a 12 × 12 ft patio
The patio uses 4 × 8 in pavers in a running bond, on well-drained soil.
- Area: 144 sq ft, with 4.5 pavers per square foot.
- Pavers: 144 × 4.5 × 1.05 = 681 pavers.
- Base: 144 × 4 ÷ 12 ÷ 27 × 1.2 = 2.13 cu yd, or 2.99 tons.
- Sand: 144 × 1 ÷ 12 ÷ 27 = 0.44 cu yd, or 0.6 tons.
- Edging: 48 ft.
- At $0.70 a paver, $40 a ton of gravel and $45 a ton of sand, materials cost about $623, or $4.33 per square foot.
Materials by patio length (12 ft wide)
| Length | Pavers | Base gravel | Cost |
|---|---|---|---|
| 8 ft | 454 | 1.42 cu yd | $415 |
| 10 ft | 567 | 1.78 cu yd | $519 |
| 12 ft | 681 | 2.13 cu yd | $623 |
| 16 ft | 908 | 2.84 cu yd | $831 |
| 20 ft | 1,134 | 3.56 cu yd | $1,038 |
Base depth
The base carries the load and drains water away, so it matters more than the pavers themselves.
- Walkways and patios on sandy, well-drained soil: 4 in of compacted crushed stone.
- Patios on clay or poorly drained soil: 6 in, often over a geotextile fabric.
- Driveways: 8 to 12 in, compacted in 2 to 3 in lifts.
Excavate deep enough for the base, the sand and the paver thickness, and slope the surface about 1/4 in per foot away from the house.
Waste by pattern
Running bond and stack bond with straight edges waste about 5%. Herringbone, basket weave and borders need more cuts, so plan for 10%. Curves, circles and fan patterns can reach 15%. Keep a few spare pavers for future repairs.
Sand: two different jobs
The bedding layer is coarse concrete sand, screeded flat to about 1 in. The joints are filled after the pavers are laid, with regular joint sand or polymeric sand, which hardens when misted and resists weeds and ants. Joint sand is not included here: one bag usually covers 25 to 75 sq ft, depending on joint width and paver size.
Edging
Without edge restraint, pavers creep outward and joints open. Use plastic or aluminum edging spiked into the base, or a concrete curb. Edges next to a house wall or an existing slab do not need it.