Installing a paver patio, walkway, or driveway requires precise material calculation across three critical layers: compacted base rock, bedding sand, and pavers themselves. This guide helps US contractors and DIY enthusiasts understand the layered system, calculate quantities accurately, and achieve a professional installation that lasts decades without settling or shifting.

Understanding the Three-Layer System

Professional paver installations use a proven three-layer structure. Each layer serves a specific purpose, and skipping steps leads to premature failure:

Layer 1: Compacted Base Rock (4-6 inches)

The foundation layer uses crushed stone (3/4" minus or Class II road base). This angular aggregate locks together when compacted, creating a stable platform that:

• Prevents settling under load (vehicles, furniture, freeze-thaw cycles)
• Provides drainage—water flows through voids between stones
• Distributes weight over native soil, preventing soft spot formation
• Resists frost heaving in cold climates

Depth guidelines: Walkways and patios need 4 inches. Driveways require 6-8 inches. Heavy equipment areas may need 12+ inches. In expansive clay soils, add 2 inches to these minimums.

Layer 2: Bedding Sand (1 inch exact)

Coarse concrete sand (not fine mason sand or play sand) provides the final leveling layer. This sand:

• Allows precise leveling with a screed board
• Fills minor voids in compacted base
• Provides a uniform bed for paver placement
• Should be exactly 1 inch after screeding (settles to 3/4 inch after pavers are compacted)

Critical: Never compact bedding sand before laying pavers. Walk on planks to avoid disturbing the screeded surface.

Layer 3: Concrete Pavers

Pavers come in dozens of sizes, but most common are:

• Standard 4×8 inch: Classic Holland stone pattern
• Jumbo 12×12 inch: Modern minimal look, faster installation
• Custom shapes: Circles, hexagons, irregular patterns

Calculating Base Rock and Sand Quantities

All granular materials are sold by the cubic yard (27 cubic feet). The formula:

Area (sq ft) × Depth (inches) ÷ 324 = Cubic yards needed

Example: 200 sq ft patio with 4 inches of base rock: 200 × 4 ÷ 324 = 2.47 yards (order 2.5-3 yards to account for compaction loss).

Compaction factor: Loose gravel compacts 15-25% when tamped. Order 20% extra to compensate. So the 2.47 yards above becomes: 2.47 × 1.2 = 2.96 yards (round up to 3).

Sand calculation: For 1-inch depth: Area (sq ft) ÷ 324 = Cubic yards. A 200 sq ft area needs: 200 ÷ 324 = 0.62 yards. Order 0.75-1 yard to account for waste and uneven base.

Paver Quantity and Joint Sand

Paver calculation: Area (sq ft) ÷ Paver area (sq ft) = Quantity. Standard 4×8 pavers: 4×8 = 32 sq inches ÷ 144 = 0.22 sq ft per paver. So 200 sq ft ÷ 0.22 = 909 pavers.

Add 10% waste for cuts, breakage, and future repairs: 909 × 1.1 = 1,000 pavers.

Joint sand (polymeric sand): This specialized sand hardens when activated with water, locking pavers together and preventing:

• Weed growth between pavers
• Ant colonies (traditional sand attracts ants)
• Paver shifting and spreading
• Joint erosion from rain and power washing

Standard calculation: 50 lbs of polymeric sand per 100 square feet of pavers. The 200 sq ft example needs: 200 ÷ 100 × 50 = 100 lbs (two 50lb bags).

Importance of Compaction: The Make-or-Break Step

The #1 failure point in DIY paver projects is inadequate compaction. Proper compaction requires:

Equipment: Rent a plate compactor (minimum 5,000 lb compaction force) for any project over 50 sq ft. Hand tampers only work for very small areas (under 20 sq ft).

Technique:

• Compact base rock in 2-inch lifts (never more than 3 inches at once)
• Make 4-6 passes over each area in different directions
• Mist with water for improved compaction (but don't create mud)
• After laying pavers, make 2-3 passes with plate compactor to set them into sand
• Use a rubber mat on compactor to prevent paver chipping

Poorly compacted base settles within 6-24 months, creating depressions that collect water and cause pavers to shift. This requires expensive tear-out and reinstallation.

Edge Restraints: The Often-Forgotten Critical Component

Pavers must have edge restraint on all sides to prevent outward creep. Options:

• Plastic paver edging: Flexible strips spiked every 12 inches ($2-4 per linear foot)
• Aluminum edge restraint: Commercial-grade, invisible profile ($4-8 per foot)
• Concrete curb: Permanent, can double as landscape border ($8-15 per foot installed)
• Soldier course: Pavers set vertically in concrete haunching (traditional method)

Never rely on landscape timbers or stones placed against paver edge—they don't provide structural restraint and pavers will spread over time.

Tips for Success

• Install landscape fabric under base rock to prevent weed growth (use commercial-grade weed barrier, not thin plastic)
• Slope base 1-2% (1/4 inch per foot) away from structures for drainage
• For driveways, use pavers rated for vehicular traffic (minimum 8,000 PSI concrete)
• Seal pavers after installation to enhance color and protect against stains (wait 60-90 days)
• Keep extra pavers for future repairs (colors and textures change between production runs)

Frequently Asked Questions