What goes under a paver patio
The calculator estimates all three layers, plus edge restraint along the perimeter, which keeps the pavers from spreading.
How the counts work
Pavers = patio area ÷ face area of one paver × (1 + waste). A 4 × 8 in paver covers 32 in², or 0.222 ft², so it takes 4.5 per square foot. The calculator ignores joint width because standard pavers have spacer nubs and very narrow joints. For wide joints, add the joint to each paver dimension.
The base is area × base depth with 10% added for compaction. Bedding sand is area × bedding depth. Edge restraint is the perimeter: 2 × (length + width). With the defaults (12 × 12 ft, 4 × 8 in pavers, 10% waste): 713 pavers, 1.96 yd³ (52.8 ft³) of base and 0.44 yd³ (12 ft³) of sand.
Bags, pallets and polymeric sand
The results also give the base and sand in store units. Base gravel weight = base volume × density (default 1.4 tons/yd³). Base bags = weight ÷ bag weight. Paver base is commonly sold in 0.5 ft³ bags of about 50 lb, for example Quikrete HardScapes Paver Base. Bedding sand bags assume about 100 lb/ft³ (1.35 tons/yd³), so a 50 lb bag is about 0.5 ft³. Polymeric joint sand: Quikrete's chart for its 50 lb Polymeric Jointing Sand (based on 4 × 8 in brick pavers) works out to roughly 40 ft² per bag for ¼ in joints and about 20–25 ft² for ½ in joints. Wider joints and smaller pavers use more, so the 40 ft² default is approximate. Pallets: coverage depends on the product and plant. Belgard lists 120 ft² (540 pieces) per pallet of 4 × 8 in Holland Stone, and Mutual Materials about 105 ft². The default is 110 ft² (approximate), so type in your supplier's figure. All of these are under "Product sizes and prices", along with optional prices for a total cost.
With the defaults (12 × 12 ft, 4 in base, 1 in sand): 2.74 tons of base, or 110 bags of 50 lb; 24 bags of bedding sand; 4 bags of polymeric sand; 2 pallets of pavers.
The results also give the base and sand in store units. Base gravel weight = base volume × density (default 1.7 t/m³). Base bags = weight ÷ bag weight (default 25 kg bags). Bedding sand bags assume about 1.6 t/m³, so a 25 kg bag is about 16 litres. Polymeric joint sand: Quikrete's chart for its 22.7 kg Polymeric Jointing Sand (based on 100 × 200 mm brick pavers) works out to roughly 3.7 m² per bag for 6 mm joints and about 2 m² for 12 mm joints. Wider joints and smaller pavers use more, so the 3.5 m² default is approximate. Pallets: coverage depends on the product and plant. Belgard lists about 11 m² (540 pieces) per pallet of 100 × 200 mm Holland Stone, and Mutual Materials about 9.7 m². The default is 10 m² (approximate), so type in your supplier's figure. All of these are under "Product sizes and prices", along with optional prices for a total cost.
With the metric defaults (3.7 × 3.7 m, 10 cm base, 3 cm sand): 2.56 tonnes of base, or 103 bags of 25 kg; 27 bags of bedding sand; 4 bags of polymeric sand; 2 pallets of pavers.
Pavers per square foot by sizePavers per square metre by size
| Paver size | Pavers per ft² | For a 12 × 12 ft patio (no waste) | With 10% waste |
|---|---|---|---|
| 4 × 8 in | 4.5 | 648 | 713 |
| 6 × 6 in | 4 | 576 | 634 |
| 6 × 9 in | 2.67 | 384 | 423 |
| 6 × 12 in | 2 | 288 | 317 |
| 12 × 12 in | 1 | 144 | 159 |
| 12 × 24 in | 0.5 | 72 | 80 |
| 16 × 16 in | 0.56 | 81 | 90 |
| 24 × 24 in | 0.25 | 36 | 40 |
| Paver size | Pavers per m² | For a 3.6 × 3.6 m patio (no waste) | With 10% waste |
|---|---|---|---|
| 10 × 20 cm | 50 | 648 | 713 |
| 15 × 15 cm | 44.44 | 576 | 634 |
| 20 × 20 cm | 25 | 324 | 357 |
| 30 × 30 cm | 11.11 | 144 | 159 |
| 40 × 40 cm | 6.25 | 81 | 90 |
| 60 × 30 cm | 5.56 | 72 | 80 |
| 60 × 40 cm | 4.17 | 54 | 60 |
| 60 × 60 cm | 2.78 | 36 | 40 |
Many pavers are sold in multi-size kits or by the square foot of coverage per pallet rather than by count. In that case, use the patio area with waste (shown in the result) and divide by the coverage the manufacturer quotes.
Base and bedding depths
- Patios and walkways: at least 4 in of compacted aggregate base over well-drained soil (ICPI Tech Spec 2). ICPI's application guide gives 4–6 in for walks.
- Residential driveways: at least 6 in, and the application guide lists 6–8 in.
- Cold climates or wet, weak soils: add 2–4 in.
- Bedding sand: 1 in uncompacted, screeded flat. Never use it to level a lumpy base.
Compact the base in lifts. ICPI describes 4–6 in lifts with a plate compactor of around 7,000 lbf, and thinner lifts with smaller machines.
Paving slabs on a mortar bed
Large concrete or stone paving slabs are often laid on a full bed of wet mortar instead of loose sand, which is the usual method in the UK. Set Bedding to Mortar (paving slabs) and the results switch from bedding sand to the mortar bed, the sharp sand and cement to mix it, and bulk bags of sand. Marshalls' installation guidelines call for a full wet bed of 1 part cement to 3 or 4 parts sharp sand, about 1¼–1½ in thick. The calculator multiplies the wet bed volume by a dry-volume factor (default 1.33) and splits it by the mix ratio. That factor and the cement density (default 90 lb/ft³) are estimating assumptions, not supplier data, and both can be edited. Bulk bags of sharp sand vary by supplier, so enter the weight printed on yours.
Large concrete or stone paving slabs are often laid on a full bed of wet mortar instead of loose sand, which is the usual method in the UK. Set Bedding to Mortar (paving slabs) and the results switch from bedding sand to the mortar bed, the sharp sand and cement to mix it, and bulk bags of sand. Marshalls' installation guidelines call for a full wet bed of 1 part cement to 3 or 4 parts sharp sand, 30–40 mm thick. The calculator multiplies the wet bed volume by a dry-volume factor (default 1.33) and splits it by the mix ratio. That factor and the cement density (default 1440 kg/m³) are estimating assumptions, not supplier data, and both can be edited. Bulk bags of sharp sand vary: Travis Perkins sells a bag of at least 800 kg, and the default is 850 kg, so enter the weight printed on yours. The sub-base is usually a crushed-rock material such as Type 1; set its density under “Product sizes, prices and costs” if your supplier quotes one.
Paving slabs on a mortar bed, 13 × 10 ft, 24 × 24 in slabsPaving slabs on a mortar bed, 3.96 × 3.05 m, 61 × 61 cm slabs
Patio length 13 ft · Patio width 10 ft · Paver length 24 in · Paver width 24 in · Waste / overage 5 % · Gravel base depth 4 in · Bedding Mortar (paving slabs) · Bedding depth 1.5 in · Base gravel density 1.4 tons/yd³ · Base gravel bag weight 50 lb · Bedding sand bag weight 50 lb · Polymeric sand coverage per bag 40 ft² · Paver pallet coverage 110 ft²Patio length 3.96 m · Patio width 3.05 m · Paver length 61 cm · Paver width 61 cm · Waste / overage 5 % · Gravel base depth 10.2 cm · Bedding Mortar (paving slabs) · Bedding depth 3.8 cm · Base gravel density 1.66 t/m³ · Base gravel bag weight 22.7 kg · Bedding sand bag weight 22.7 kg · Polymeric sand coverage per bag 3.72 m² · Paver pallet coverage 10.22 m²
- Pavers needed: 35
- Mortar bed (wet volume): 0.6 yd³ (16.3 ft³)Mortar bed (wet volume): 0.46 m³ (460 L)
- Sharp sand for the mortar: 0.86 tonsSharp sand for the mortar: 0.78 tonnes
- Cement bags (94 lb each): 5Cement bags (42.6 kg each): 5
How much extra to order
Cuts at edges, curves and patterns drive waste. As a rule of thumb, use about 5–10% for a square patio laid in running bond with few cuts, 10–15% for herringbone, basketweave or diagonal layouts, and more for curves, fire pits and circles. Keep a few spare pavers for future repairs, since colours vary between production runs.
Worked examples
Patio, 12 × 16 ft, 6 × 9 in pavers, herringbonePatio, 3.66 × 4.88 m, 15.2 × 22.9 cm pavers, herringbone
Patio length 16 ft · Patio width 12 ft · Paver length 9 in · Paver width 6 in · Waste / overage 15 % · Gravel base depth 4 in · Bedding depth 1 in · Base gravel density 1.4 tons/yd³ · Base gravel bag weight 50 lb · Bedding sand bag weight 50 lb · Polymeric sand coverage per bag 40 ft² · Paver pallet coverage 110 ft²Patio length 4.88 m · Patio width 3.66 m · Paver length 22.9 cm · Paver width 15.2 cm · Waste / overage 15 % · Gravel base depth 10.2 cm · Bedding depth 2.5 cm · Base gravel density 1.66 t/m³ · Base gravel bag weight 22.7 kg · Bedding sand bag weight 22.7 kg · Polymeric sand coverage per bag 3.72 m² · Paver pallet coverage 10.22 m²
- Pavers needed: 589
- Gravel base (incl. 10% compaction): 2.61 yd³ (70.4 ft³)Gravel base (sub-base, e.g. Type 1 or crushed rock; incl. 10% compaction): 1.99 m³
- Bedding sand: 0.59 yd³ (16 ft³)Bedding sand: 0.453 m³ (453 L)
- Edge restraint length: 56 ftEdge restraint length: 17.1 m
Walkway, 30 × 4 ft, 4 × 8 in paversWalkway, 9.14 × 1.22 m, 10.2 × 20.3 cm pavers
Patio length 30 ft · Patio width 4 ft · Paver length 8 in · Paver width 4 in · Waste / overage 10 % · Gravel base depth 4 in · Bedding depth 1 in · Base gravel density 1.4 tons/yd³ · Base gravel bag weight 50 lb · Bedding sand bag weight 50 lb · Polymeric sand coverage per bag 40 ft² · Paver pallet coverage 110 ft²Patio length 9.14 m · Patio width 1.22 m · Paver length 20.3 cm · Paver width 10.2 cm · Waste / overage 10 % · Gravel base depth 10.2 cm · Bedding depth 2.5 cm · Base gravel density 1.66 t/m³ · Base gravel bag weight 22.7 kg · Bedding sand bag weight 22.7 kg · Polymeric sand coverage per bag 3.72 m² · Paver pallet coverage 10.22 m²
- Pavers needed: 594
- Gravel base (incl. 10% compaction): 1.63 yd³ (44 ft³)Gravel base (sub-base, e.g. Type 1 or crushed rock; incl. 10% compaction): 1.25 m³
- Bedding sand: 0.37 yd³ (10 ft³)Bedding sand: 0.283 m³ (283 L)
Driveway, 40 × 12 ft, 4 × 8 in, 8 in baseDriveway, 12.2 × 3.66 m, 10.2 × 20.3 cm, 20.3 cm base
Patio length 40 ft · Patio width 12 ft · Paver length 8 in · Paver width 4 in · Waste / overage 8 % · Gravel base depth 8 in · Bedding depth 1 in · Base gravel density 1.4 tons/yd³ · Base gravel bag weight 50 lb · Bedding sand bag weight 50 lb · Polymeric sand coverage per bag 40 ft² · Paver pallet coverage 110 ft²Patio length 12.19 m · Patio width 3.66 m · Paver length 20.3 cm · Paver width 10.2 cm · Waste / overage 8 % · Gravel base depth 20.3 cm · Bedding depth 2.5 cm · Base gravel density 1.66 t/m³ · Base gravel bag weight 22.7 kg · Bedding sand bag weight 22.7 kg · Polymeric sand coverage per bag 3.72 m² · Paver pallet coverage 10.22 m²
- Pavers needed: 2,333
- Gravel base (incl. 10% compaction): 13.04 yd³ (352 ft³)Gravel base (sub-base, e.g. Type 1 or crushed rock; incl. 10% compaction): 9.97 m³
- Bedding sand: 1.48 yd³ (40 ft³)Bedding sand: 1.13 m³
Driveway pavers are typically thicker than patio pavers. ICPI notes 3⅛ in units for vehicular use.Driveway pavers are typically thicker than patio pavers. ICPI notes 80 mm units for vehicular use.
Cutting safely
Cutting concrete pavers with a saw releases respirable crystalline silica. OSHA's guidance for handheld saws is to cut wet, with water fed continuously to the blade, and in some situations to wear a respirator as well. Wear eye and hearing protection. A splitter (guillotine) avoids dust for straight cuts on many paver types.
Edge restraint and joint sand
Interlocking pavers need a solid edge to keep them from spreading. ICPI's construction guide calls for edge restraints around the perimeter, such as plastic or metal edging spiked into the base, or a concrete curb. The calculator gives the edge restraint length as the patio perimeter. Subtract any sides that butt against a house foundation or existing concrete. After the pavers are laid and compacted, sweep joint sand into the joints and compact again so the joints fill. Polymeric sand (sand with a binder) resists washout and weeds. Follow the manufacturer's directions on joint width, dryness and wetting.
Checked against
Each case below is re-run against the calculator by our automated test suite.
| Case | Our result | Checked against | Result |
|---|---|---|---|
| 120 ft² of 4 × 8 in pavers, no waste | 540 | Belgard product guide: Holland Stone pieces and coverage per pallet | Match |
| 12 × 12 ft patio, 4 × 8 in pavers, no waste | 648 | Hand calculation | Match |
| Case | Our result | Checked against | Result |
|---|---|---|---|
| 11.1 m² of 10.2 × 20.3 cm pavers, no waste | 540 | Belgard product guide: Holland Stone pieces and coverage per pallet | Match |
| 3.66 × 3.66 m patio, 10.2 × 20.3 cm pavers, no waste | 648 | Hand calculation | Match |
Frequently asked questions
How many pavers per square foot?
Divide 144 by the paver's face area in square inches. 4 × 8 in = 4.5 per ft², 6 × 6 = 4, 12 × 12 = 1.
How many pavers for a 12 × 12 patio?
With 4 × 8 in pavers, 648 before waste, or 713 with 10%.
How much base do I need for pavers?
ICPI: at least 4 in compacted for patios and 6 in for driveways on well-drained soil, more in cold or wet conditions.
How much sand for pavers?
About 1 in of bedding sand, which is 1 ft³ per 12 ft², plus jointing sand per the bag's coverage chart.
Sources & assumptions
The results are planning estimates, and the cost figures only use prices you enter. Product yields, densities and coverage rates vary, so check the label or ask your supplier, and follow local codes. Figures marked "approximate" or "rule of thumb" are general practice, not exact standards.
- ICPI Tech Spec 2: Construction of Interlocking Concrete Pavements
- ICPI Tech Spec 10: Application Guide for Interlocking Concrete Pavements
- Quikrete HardScapes Paver Base, 0.5 ft³ / 50 lb bag (retail listing)
- Quikrete Polymeric Jointing Sand (50 lb) coverage chart
- Belgard product guide: Holland Stone 4 × 8 in, 120 ft² and 540 pieces per pallet
- Mutual Materials Holland paver tech sheet: 486 pieces, about 105 ft² per pallet
- Marshalls Concrete Paving Installation Guidelines (full mortar bed: 1 cement to 3–4 sharp sand)
- Travis Perkins sharp sand bulk bag (minimum 800 kg)
- OSHA fact sheet: Controlling silica dust from handheld power saws
See how we calculate and test our formulas and the changelog. Last updated 2026-10-08.
Reviewed by the MaterialWhiz Editorial Team. This estimate uses the assumptions shown in the calculator. Review the result against your supplier's product coverage and site conditions. Last reviewed: October 10, 2026. See how we calculate · Report a correction.