Paver Base Calculator

To calculate paver base material: (1) Determine the total excavation footprint in square feet (paver surface area plus horizontal base extension beyond edge restraints). (2) Multiply base footprint area by the desired compacted base depth in feet (depth in inches divided by 12) to find compacted cubic feet. (3) Divide cubic feet by 27 to get compacted cubic yards. (4) Add a 10% to 20% loose-order allowance (typically 15%) to compensate for vibratory plate compaction shrinkage and grade variance. (5) Multiply loose cubic yards by the planning density (typically 1.35 to 1.45 tons per cu yd, averaging 1.40 tons/yd³) to determine order tonnage.

Industry guidance from CMHA PAV-TEC-002 (formerly Tech Spec 2) recommends a minimum 4-inch compacted aggregate base for pedestrian patios, walkways, and pool decks over well-drained native soils. For residential vehicular driveways, CMHA guidance recommends at least 6 to 8 inches of compacted base on well-drained soils, increasing to 10 to 12 inches (or utilizing geotextile stabilization fabric) over heavy clay subgrades, poor drainage areas, or freeze-thaw climates. Base depth must always be configured according to site-specific subgrade stability, drainage, and load requirements.

Compacted Design Volume represents the solid, in-place finished thickness of the gravel base layer after mechanical plate compaction. Planning Order Volume accounts for the uncompacted bulk material delivered from the quarry or supplier and potential grade variances. Crushed dense-graded aggregate compacts under vibratory rollers or plate compactors, typically leading contractors to select a planning order allowance of 10% to 20% (with 15% as a common preset). Ordering based purely on in-place compacted dimensions may result in a shortage of delivered material on site.

Extending the compacted aggregate base horizontally beyond the paver area is a derived planning method to provide solid foundation support for edge restraints and anchoring spikes. In physical installations (Paver Edge → Restraint → Stake → Base Edge), CMHA Tech Note PAV-TEC-003-22 notes that for spiked restraints on flexible base, the base should extend past the restraint at least the same dimension as the base thickness, and that the distance from stakes to base perimeter should be consistent (typically not exceeding 10 inches on residential projects). This ensures steel spikes drive firmly into compacted aggregate rather than soft uncompacted subgrade.

One cubic yard of loose dense-graded crushed stone base aggregate (such as Crusher Run, Road Base #21A, ABC, or 3/4-inch minus with fines) typically weighs between 1.35 and 1.45 US short tons (2,700 to 2,900 lbs), averaging 1.40 tons per cubic yard (~103.7 lbs per cubic foot). Actual density varies based on parent quarry geology (limestone, granite, basalt, or recycled concrete) and moisture content.

Always use dense-graded crushed aggregate meeting ASTM D2940 specifications, commonly sold locally as Road Base #21A, Crusher Run, 3/4-inch Minus, Class 5, or Aggregate Base Course (ABC). Dense-graded aggregate contains a continuous distribution of stone particles ranging from 3/4-inch angular rocks down to minus-200 stone dust fines. When compacted with water, the angular fines fill all voids and interlock into an unyielding, load-distributing foundation. Never use rounded pea gravel, uniform clean stone (unless designing an open-graded permeable pavement), or mason sand as a sub-base.

Our calculator decomposes L-shaped footprints into two non-overlapping orthogonal sections (Section 1: Length 1 × Width 1; Section 2: Length 2 × Width 2) to eliminate double-counting the seam. For multi-section layouts, each rectangular section is calculated independently and summed into the total footprint. You can then apply a full perimeter base extension or specify the exact linear footage of unconfined borders requiring edge restraint anchoring.