Calculate exactly how much base gravel and bedding sand you need for a perfect paver installation.
Enter your project dimensions and traffic type
Enter your project area and select the traffic type, pedestrian (4-inch base) or vehicle (6-inch base). The calculator automatically applies industry-standard depths for both gravel base and bedding sand. For custom depths, select "Custom" and enter your own values. Results show cubic yards and approximate tons for each material.
The base is the most important part of any paver project. A properly compacted base prevents pavers from shifting, sinking, and cracking over time. Skimping here means redoing the project in 3-5 years, doing it right now means decades of durability.
A proper paver base has two layers. The gravel base (4-6 inches of crushed stone) provides structural support and drainage. On top of that, a bedding sand layer (1 inch of coarse sand) lets you fine-tune each paver's level during installation. Never use sand alone as a base, it erodes and shifts under load.
For a 20×15 foot (300 sq ft) patio, you'd need roughly 3.7 cubic yards of base gravel and 0.9 cubic yards of bedding sand, costs typically run $150-250 for materials.
Compaction is not optional. A plate compactor (vibratory tamper) is required, a hand tamper is insufficient for anything beyond a tiny walkway. Compact the subgrade soil first, then add base gravel in 2-inch lifts, compacting each lift separately before adding the next. Trying to compact 6 inches of gravel at once only compacts the top 2 inches. The finished base should be so firm that a heel leaves no impression. After compacting, screed the bedding sand (do NOT compact the sand layer, pavers are bedded into loose sand and then compacted together at the end). After placing all pavers, run the plate compactor over the surface (with a rubber mat or carpet scrap to protect paver faces) to vibrate them into the sand bed, then sweep polymeric sand into the joints, compact again, and mist with water to activate.
Without a solid edge restraint, pavers gradually migrate outward, especially along curves and driveway edges. Use plastic or aluminum paver edging secured with 10-12" galvanized spikes driven into the compacted base (not just the soil). The edging should sit flush with or slightly below the paver surface. For driveways, use concrete haunching, a triangular wedge of concrete poured against the outer edge of the pavers, which provides far more lateral resistance than spike-in edging alone. Never skip edge restraint on any paver installation, regardless of size.
All paver surfaces must slope away from structures. The standard is 1/4" per foot (2% grade) minimum for pedestrian areas, and 1/8" to 1/4" per foot for vehicular areas. This slope is built into the base layer, the sand bedding follows the base slope. For patios adjacent to a house, slope away from the foundation. For a 20-foot-deep patio, the outer edge should be 5 inches lower than the house edge. Build this into your excavation, digging the base evenly deep and then adding slope via gravel thickness doesn't work because the gravel layer would be different thicknesses, creating uneven compaction.