Paver & Block Paving Sand Calculator
Calculate bedding sand, jointing sand, and sub-base quantities for block paving, natural stone, and concrete paver projects — with instant metric and imperial results.
This version breaks the job into sub-base, bedding sand, and jointing sand so the output matches a real paving build-up.
Paved area
Joint details
Allowance
Results
Enter the project details to calculate the result for this tool.
Paver & Block Paving Sand Calculator
Calculate bedding sand, jointing sand, and sub-base quantities for block paving, natural stone, and concrete paver projects — with instant metric and imperial results.
The paver and block paving sand calculator estimates the total sand required for a paving project in 2 layers: the compacted bedding layer (typically 25–50 mm of sharp sand) and the jointing layer swept into the paver gaps after laying. Input the paved area dimensions and the number of paving units to get precise quantities for both layers. Bedding sand (coarse sharp sand) has a density of 1,680 kg/m³. Jointing sand (kiln-dried fine sand or polymeric sand) has a density of 1,500 kg/m³. The calculator outputs cubic metres, cubic yards, cubic feet, kilograms, and pounds.
Why Calculate Paving Sand Before You Start?
Block paving projects fail most often due to incorrect sand depths and under-ordered jointing material. There are 5 reasons to calculate paving sand quantities precisely:
- Correct bedding depth — the bedding layer must be 25–50 mm (1–2 in) thick after compaction; over-ordering bedding sand leads to instability and under-ordering causes subsidence.
- Jointing sand coverage — gaps between pavers hold kiln-dried sand; a 10 m² paved area with standard block paving (200 × 100 mm blocks) requires approximately 25 kg of jointing sand.
- Sub-base accuracy — MOT Type 1 sub-base typically goes 100–150 mm deep under block paving; the calculator cross-checks your sand layer against total excavation depth.
- Material cost control — bedding sand, jointing sand, and sub-base are ordered separately; combining all 3 quantities into one estimate prevents double-ordering.
- Supplier compatibility — UK suppliers sell bedding sand by the tonne; the calculator converts cubic metres to tonnes using the correct compacted density.
How Much Bedding Sand Do I Need for Block Paving?
Multiply the paved area (m²) by the bedding depth in metres. For a 20 m² driveway with a 40 mm (0.04 m) bedding layer: 20 × 0.04 = 0.8 m³ of loose sand. After compaction, sand reduces by 15–20%, so order 0.96 m³ (approximately 1 m³) to allow for compaction loss. At 1,680 kg/m³, that equals approximately 1,680 kg (1.68 tonnes) of bedding sand.
How Much Jointing Sand Do I Need?
Jointing sand fills the 2–3 mm gaps between paving blocks. Coverage depends on the block size and joint width. For standard 200 × 100 mm blocks with 2 mm joints, approximately 2–3 kg of kiln-dried sand per m² is required. For 10 m² that equals 20–30 kg (1 to 1.5 bags of 25 kg). After sweeping, a second application is often needed once the sand settles. Polymeric jointing sand (for permanent locking) is applied at the same rate but cures to a semi-rigid joint.
Block Paving Sand Depth by Application
Footpaths and pedestrian areas: bedding sand 25 mm, sub-base 100 mm MOT. Residential driveways: bedding sand 30–40 mm, sub-base 150 mm MOT. Commercial areas with light vehicle traffic: bedding sand 50 mm, sub-base 200 mm MOT. Natural stone paving (granite, sandstone, slate) uses a wet mortar bed (1:6 cement:sand) at 30–50 mm depth instead of loose sand — enter your mortar dimensions into the calculator using masonry sand density (1,650 kg/m³).
Sand types and densities
Use the table as a quick guide when choosing a material setting for your project.
| Material | kg/m³ | Common Use |
|---|---|---|
| Sand, dry | 1,600 kg/m³ | Multi-purpose sand. Used for joint filling, equestrian arena footing, and general construction. |
| Sand, wet | 1,920 kg/m³ | Unprocessed sand. Used for backfilling, leveling, and trench support. |
| Sand, packed | 1,680 kg/m³ | Coarse, angular sand. Used under pavers, flagstone, and stepping stones at 25–50 mm depth. |
| Concrete sand | 1,500 kg/m³ | Coarse, washed sand. Used for concrete mixing, drainage layers, and pipe bedding. |
| Masonry sand | 1,650 kg/m³ | Fine, screened sand. Used for mortar mix, brick laying, stucco, and finishing work. |
| Fill sand | 1,750 kg/m³ | Unprocessed sand. Used for backfilling, leveling, and trench support. |
Paver & Block Paving Sand FAQs
Common questions about calculating sand quantities for block paving, patio stone, and driveway laying.
Coarse sharp sand (also called grit sand or concrete sand) is used as the bedding layer under block paving. It must not contain clay, silt, or fine particles. Sharp sand compacts firmly and resists water erosion. Do not use soft building sand (masonry sand) as a bedding layer — it is too fine and will wash out under load.
The bedding layer under block pavers should be 25–50 mm (1–2 inches) of compacted sharp sand. For residential driveways, 40 mm is the most common depth. For pedestrian footpaths, 25 mm is sufficient. The sand must be screeded flat to a consistent depth before laying blocks.
Kiln-dried sand (also called jointing sand or dry sand) is swept into the joints between blocks after the paving is laid and compacted. It fills the 2–3 mm gaps and locks the blocks together. It must be bone dry when applied — applying damp jointing sand causes clumping and joint failure.
A 50 m² patio with a 40 mm bedding layer requires approximately 2.0 m³ of sharp sand. At 1,680 kg/m³, that is approximately 3.36 tonnes. Adding a 15% compaction factor brings the order to approximately 3.9 tonnes. Jointing sand adds approximately 100–150 kg (0.1–0.15 tonnes) for standard block joints.
Sharp sand is used for bedding and sub-base work. Building sand (soft sand / masonry sand) is used for pointing between natural stone flags and for mortar joints. For block paving joints, use kiln-dried sand or polymeric sand — not mortar.
Polymeric sand is kiln-dried jointing sand with polymer binders added. When activated with water, the polymers cure to form a semi-rigid, weed-resistant, and insect-resistant joint. It is used in areas prone to weed growth, heavy rainfall, or high foot traffic. It costs 3–5× more than standard kiln-dried sand but lasts significantly longer.
For a circular area, calculate the area using the formula: Area = π × radius². For a 3 m radius circle: Area = 3.14159 × 9 = 28.27 m². Multiply by the bedding depth to get volume. The Sand Calculator on this page handles circular shapes automatically using the circle shape button.