How the paver calculator works
Pavers = area × (1 + waste) ÷ area of one paver
Base = (area + edge length × base depth) × base depth, in cubic yards; tons = cubic yards × 1.4
Sand = area × sand depth ÷ 0.5 cu ft per bag
Worked example
A 12 by 12 foot patio is 144 sq ft. Each 4 by 8 inch paver covers 0.222 sq ft, so with 10% extra you need 713 pavers. A 4 inch base that runs past the 48 feet of edges is about 1.98 cubic yards, or 2.8 tons of crushed stone. One inch of sand is 12 cubic feet, or 24 bags.
Layer by layer
| Layer | Typical depth | Notes |
|---|---|---|
| Compacted crushed stone base | 4 to 6 in for patios and walks; 8 to 12 in for driveways | Extends past the edges by about its own depth |
| Bedding sand | About 1 in | Screeded level, not compacted before laying |
| Pavers | 2 3/8 in common | Then compacted into the sand |
| Joint sand | Fills the joints | Polymeric sand hardens when wetted |
Base depths follow guidance from paver maker Unilock.
Before you buy
- Order pavers from one production run so colors match, and keep a few spares.
- Rent a plate compactor; hand tamping rarely gets a base firm enough.
- Slope the patio about 1/4 inch per foot away from the house for drainage.
Common questions
How many pavers do I need for a 12x12 patio?
A 12 by 12 patio is 144 sq ft. Standard 4 by 8 inch pavers cover 0.22 sq ft each, so you need 648, or 713 with 10% extra for cuts.
How deep should the base be for pavers?
About 4 to 6 inches of compacted crushed stone for patios and walkways, and 8 to 12 inches for driveways, according to paver maker Unilock. Clay soils may need more.
How much sand do I need under pavers?
A bedding layer about 1 inch deep is common. 144 sq ft at 1 inch is 12 cubic feet, or 24 bags of 0.5 cubic feet.
How much extra should I order for cuts?
About 5 to 10% for straight patterns and 15% for herringbone or curved edges.