Patio paver calculator
Build the patio from rectangles, circles and triangles, pick the paver and pattern, and get the pavers to order with the gravel base, bedding sand and how deep to dig.
Materials to order
168 ft² of 8 in × 4 in pavers, 1/8 in joints, herringbone 90° with 10% for cuts; 4 in base, 1 in bedding sand.
- Pavers794722 laid + 10% for cuts
- Base aggregate3.52 US tons (7,048 lb)2.49 yd³ (67.2 ft³) loose
- Bedding sand1,359 lb0.52 yd³ (14 ft³)
Herringbone 90°, 8 in × 4 in pavers with 1/8 in joints: one paver plus its joint covers 33.5 in².
| Item | Quantity | Notes |
|---|---|---|
| Paved area | 168 ft² | edge restraint about 52 ft |
| Pavers | 794 | 4.3 per ft² with joints |
| Base, compacted | 2.07 yd³ (56 ft³) | 4 in deep |
| Base to order | 2.49 yd³ (67.2 ft³) | +20% for compaction · 3.52 US tons (7,048 lb) · 141 × 50 lb bags |
| Bedding sand | 0.52 yd³ (14 ft³) | 1 in screeded · 1,359 lb · 28 × 50 lb bags |
| Dig out | 3.82 yd³ (103.3 ft³) | 7 3/8 in deep (base + sand + paver) |
Weights use loose dry gravel and dry sand; damp sand weighs more, and quarries quote their own figures. Joint sand is extra: follow its bag.
How to use the paver calculator
Describe the patio as shapes: rectangles (length × width), circles and half circles (diameter) and triangles (base × height). Add one for each part, and tick Cut-out for a planting bed or a tree that the paving goes around. A patio with a round end is a rectangle plus a half circle as wide as the rectangle.
Enter the paver's real size, the joint between pavers and the pattern. Each paver plus its joint covers a little more than the paver itself, which is how the count per square foot or metre is worked out. The cutting allowance starts at our rule-of-thumb figure for the pattern (5% for running bond up to 15% for herringbone at 45°) and goes up for curves and many corners.
Base and bedding
The base is crushed aggregate compacted in layers. The calculator orders 20% more loose stone than the compacted volume, a common allowance you can change, and converts it to weight with the density you give; quarries quote their own. Bedding sand is screeded about 1 in (25 mm) deep. The dig depth adds base, sand and paver thickness.
Worked example
A 14 × 12 ft patio is 168 ft². An 8 × 4 in paver with 1/8 in joints covers 8.125 × 4.125 = 33.5 in², so 4.3 pavers per ft²: 722 laid, 794 with 10% for herringbone. A 4 in base is 56 ft³ compacted, 67 ft³ to order, about 3.5 tons.
How thick should the base be?
The Concrete Masonry & Hardscapes Association (CMHA), which took over the Interlocking Concrete Pavement Institute's technical guides, sets a minimum compacted base of 4 in (100 mm) for patios and walks on well-drained soil, and at least 6 in (150 mm) for residential driveways. Cold climates and wet or weak soils need more. Bedding sand is spread and screeded to an uncompacted 1 in (25 mm), joints between concrete pavers are 1/16 to 3/16 in (2 to 5 mm), and pedestrian areas and driveways use units 2 3/8 in (60 mm) thick.
Choosing "Residential driveway" above sets the base to 6 in (150 mm). If your ground drains poorly or freezes hard, ask a local supplier or contractor what works there.
Sources
- Concrete Masonry & Hardscapes Association, Construction of Interlocking Concrete Pavements (PAV-TEC-002-22): base thickness, bedding sand depth, joint widths and paver thickness.
- The Engineering ToolBox, Earth, soil and water densities: dry gravel 105 lb/ft³ (1,680 kg/m³), dry sand 97 lb/ft³ (1,555 kg/m³), wet sand 119 lb/ft³ (1,905 kg/m³).
Questions
How many pavers do I need for a 10 × 10 ft patio?
With 8 × 4 in pavers and 1/8 in joints, 100 ft² takes about 430 pavers laid. Add 5% for running bond (452) or 10% for herringbone (473). Larger pavers bring the count down fast: 12 × 12 in slabs need about 98 before cuts.
How much gravel goes under pavers?
CMHA's minimum is 4 in (100 mm) of compacted aggregate for patios and walks on well-drained soil, and 6 in (150 mm) for residential driveways. Order more loose stone than the compacted volume, because it settles as it is compacted in layers.
Why does herringbone need more pavers?
It doesn't need more in the field, but every edge cuts across the pattern at an angle, so more pavers are cut and more offcuts are too small to reuse. The 45° version cuts every edge paver. That is why its allowance here starts at 15%.
Is joint sand included?
No. The bedding sand under the pavers is included; the finer or polymeric sand swept into the joints is not, because how much it takes depends on the joint width and the paver's edges. Its bag gives the coverage.