Paver Base Calculator
This paver base calculator gives the gravel base and bedding sand a patio, walkway or driveway needs, each material separately, in cubic yards and tons.
Patio or Walkway
Driveway
Vehicle loads need a deeper base, laid and compacted in layers rather than all at once.
Base and Sand Cost
How to use the Paver Base Calculator
Measure the area the pavers will cover, then set two depths: the compacted gravel base underneath, and the bedding sand between the base and the pavers.
Four inches of base is the usual figure for a patio or walkway, six over soft or frost-prone ground, and eight or more for anything a car drives on. The bedding course is one inch, always, it is a levelling layer, not part of the structure.
The compaction allowance covers what the base loses when it is rolled. You are ordering loose material to end up with a compacted depth, so the order is larger than the finished thickness suggests.
Base and Sand Cost keeps the two materials on separate lines, because they are separate orders at different prices. The compaction allowance applies to the base only, bedding sand is screeded, not rolled.
Paver Base formula
Each layer is its own volume:
base = length × width × base depth × (1 + compaction%)sand = length × width × bedding depth × (1 + waste%)cubic yards = cubic feet ÷ 27
Weights use each material’s own density:
- Crushed base rock: 2,900 lb per cubic yard (1.45 tons)
- Coarse bedding sand: 2,650 lb per cubic yard (1.33 tons)
Excavation depth is the two layers plus the paver itself:
dig depth = base + bedding + paver thickness
Worked example
A 16 ft × 12 ft patio on a 4 inch base with 1 inch of bedding sand:
- Area: 16 × 12 = 192 sq ft
- Base: 192 × 0.3333 = 64 ft³ = 2.37 yd³, plus 20% compaction = 2.84 yd³ (about 4.12 tons)
- Sand: 192 × 0.0833 = 16 ft³ = 0.59 yd³, plus 5% = 0.62 yd³ (about 0.82 tons)
A 20 ft square driveway on an 8 inch base needs about 11.85 yd³ of base rock and 1.30 yd³ of sand.
What the result means
These are two separate orders. The base is crushed angular rock with fines, road base, crusher run, or a product sold as paver base. The bedding is coarse concrete sand. Neither substitutes for the other, and a yard delivering one pile when you needed two is a wasted day.
The volumes are exact geometry. The tonnages are estimates, because loose aggregate density moves with moisture and source. The compaction allowance is likewise a working figure rather than a constant: twenty percent is typical for crushed base rolled in lifts, but it depends on the material and how hard it is compacted.
Excavation goes deeper than either layer. Add the paver thickness on top of base plus bedding to get the depth to dig.
Common mistakes
- Using bedding sand as base. Sand does not compact into a structural layer. It is the levelling course and nothing else.
- Laying bedding sand thicker than an inch. The single most common cause of a settled, wavy patio. Screed to one inch and correct grade in the base, not the sand.
- Compacting the base in one lift. A plate compactor only reaches three or four inches down. An eight inch base goes in as two layers, each compacted.
- Skipping the compaction allowance. Order to the finished depth and you will be a fifth short and back at the yard.
- Forgetting the paver thickness when excavating. Dig depth is base plus bedding plus the paver, or the finished surface sits proud of the grade.
Frequently asked questions
How deep should a paver base be?
Four inches of compacted base for a patio or walkway, six inches over soft ground or in cold climates, and eight to twelve inches for a driveway. One inch of bedding sand sits on top of the base in every case.
How much paver base do I need for a 12×16 patio?
On a 4 inch base, 192 square feet works out at 64 cubic feet or 2.37 cubic yards, which is about 2.84 cubic yards ordered loose once you allow 20 percent for compaction, roughly 4.1 tons. You also need about 0.62 cubic yards of bedding sand.
How much does a yard of paver base weigh?
Crushed base rock runs about 2,900 lb per cubic yard, so roughly 1.45 tons. Coarse bedding sand is lighter at about 2,650 lb, or 1.33 tons. Wet material weighs more.
How deep do I dig for pavers?
Base depth plus one inch of bedding sand plus the paver thickness. A patio on a 4 inch base with 2 3/8 inch pavers means excavating about 7 3/8 inches below the finished surface.
Can I use sand instead of paver base?
No. Sand is not a structural layer, it shifts under load and washes out. The base is compacted crushed rock with fines, which locks together. Sand only ever goes in as the one inch levelling course on top.
Why order more base than the finished depth?
Because crushed base loses roughly a fifth of its loose volume when it is compacted. Ordering to the finished depth leaves you short. Twenty percent is the usual allowance.
Sources and assumptions
Volumes are exact geometry. Densities are mid-range values from aggregate supply charts: crushed base rock at about 2,900 lb per cubic yard and coarse sand at about 2,650.
Base depth guidance follows standard segmental paving practice, four inches for pedestrian areas, more for vehicular loads, soft subgrades and freeze-thaw regions. Local conditions and manufacturer specifications take precedence over any general figure.
The compaction allowance is a working estimate and varies with material and effort. Confirm quantities with your supplier before ordering.