Patio Paver Calculator

How many patio pavers do you need?

Counting patio pavers is straightforward once you know the formula, but skipping the waste allowance is the mistake that sends most DIY pavers back to the supplier mid-project. First find your patio area by multiplying length by width in metres. Then find the area of one paver in square metres by converting its centimetre dimensions to metres and multiplying them. Divide patio area by paver area to get the base count, then add a waste percentage for cuts, breakages, and awkward edges. A 12 square metre patio laid with 20 by 10 centimetre pavers needs 600 pavers before waste, and 660 with a 10 percent allowance for a herringbone pattern. Buying the base count only guarantees a shortfall, because no patio is cut-free.

Waste percentage depends on pattern more than anything else. A simple running bond or stretcher pattern, where pavers run in straight rows, wastes about 5 percent, since most cuts happen only at the edges. A basket weave or stack bond wastes around 7 percent, while herringbone, the most attractive and the most complex pattern, wastes 10 percent or more, because every edge produces angled offcuts that cannot be reused. Circular patios, curved edges, and patios with steps, drains, or planting holes all waste more, so add another 2 to 3 percent for each complication. It is always cheaper to have a few pavers left over than to run out and discover the supplier's new batch is a slightly different shade.

Choosing a paver size

Paver size changes the look, the laying speed, and the count dramatically. Small pavers of 20 by 10 centimetres suit intricate patterns like herringbone and basket weave, and they handle curves gracefully, but they take far longer to lay and need many more units. Large slabs of 60 by 60 centimetres or 90 by 60 centimetres lay quickly, suit modern minimalist patios, and need far fewer units, but they show lippage, small height differences, more readily and they are heavy to handle. Medium pavers of 30 by 30 centimetres or 40 by 40 centimetres are a good compromise for most DIY projects, balancing speed, pattern options, and manageable weight.

Patterns and their trade-offs

Running bond is the easiest pattern for beginners: pavers run in rows with joints staggered by half a paver, which is forgiving of small errors and looks tidy. Stack bond, with pavers aligned in a strict grid, looks ultra-modern but shows every misalignment, so it suits experienced layers and perfectly square patios. Herringbone, where pavers interlock at right angles, is the strongest pattern under load, which is why it is used for driveways, and it looks superb, but it is slow and wasteful. Basket weave alternates pairs of horizontal and vertical pavers for a woven look that suits traditional gardens. Whichever pattern you choose, lay a trial section first to check the look and your speed before committing to the whole patio.

Base, drainage, and levels

Pavers are only as good as what lies beneath them. A proper patio base is usually 100 to 150 millimetres of compacted hardcore, topped with a sharp sand or mortar bed, and it must fall away from the house at a gradient of about 1 in 60 so rainwater drains off rather than pooling against the walls. Skipping the base or laying pavers directly on soil guarantees sinking, rocking, and weed growth within a year. Check for drains, manhole covers, and utility access points before you start, since these need to remain accessible and may need recessed covers that match your paver pattern. Always check levels with a spirit level and a string line as you go, not at the end.

Materials: concrete, stone, porcelain, and clay

Concrete pavers are the cheapest and most consistent option, available in many colours and textures, though some fade over time and cheaper ones can look flat. Natural stone, such as sandstone, limestone, and granite, looks superb and ages gracefully, but it varies in colour and thickness, costs more, and needs sealing to resist staining. Porcelain pavers are slim, stain-resistant, and available in realistic stone and wood effects, but they need a solid concrete base and specialist adhesive, since they cannot be laid on sand alone. Clay pavers are dense, durable, and rich in colour, and they suit traditional homes, but they are smaller and slower to lay. Choose material for your climate as well as your taste, since freeze-thaw cycles crack porous stone that is fine in mild areas.

Jointing, sealing, and finishing

Joints do more than fill gaps: they lock pavers together, allow for thermal movement, and stop weeds. Brush-in jointing sand is the simplest option for concrete pavers, while resin-based jointing compounds resist weeds and ants better and suit natural stone. Keep joints consistent, usually 3 to 5 millimetres for pavers and wider for large slabs, since uneven joints are the first thing the eye notices. Sealing is optional but worthwhile for porous stone and light colours, since it resists stains from food, leaves, and barbecue grease. Seal only when the patio is fully dry and clean, and test the sealer on a spare paver first, since some sealers darken stone noticeably.

Ordering, delivery, and storage

Order pavers by the calculated count, rounded up to the supplier's pack size, since suppliers sell in packs and a part-pack is rarely available. Check delivery access before ordering: a pallet of pavers weighs over a tonne, and the delivery vehicle needs to reach your garden or a nearby hard standing. Store pavers flat, on a level surface, protected from rain if they are porous stone, and keep a few spares after the project for future repairs, since matching a batch years later is difficult. Inspect the delivery on arrival, since damaged or wrong-colour pavers are far easier to replace before laying starts than after half the patio is down.

Cost estimation beyond pavers

The pavers themselves are often less than half the total project cost. Budget for hardcore, sand or mortar, jointing compound, edging restraints, and possibly a membrane, plus tool hire for a plate compactor and a wet saw if you do not own them. Labour, if you hire a layer, usually exceeds materials, so get several quotes and check previous work in person. A common budgeting mistake is forgetting edging: without a solid edge restraint, the outer pavers spread and sink, so include edging blocks or a concrete haunch in your plan and your budget from the start.

Small patios and balconies

Small patios need the same waste logic as large ones, but the percentage matters more, since a single cut can be a large share of a tiny area. For patios under 5 square metres, add at least 10 percent waste regardless of pattern, and consider larger pavers to reduce joint count and laying time. On balconies, check the weight limit before choosing thick stone pavers, and consider porcelain tiles or deck tiles instead, since they are lighter and thinner while giving a similar look.

Maintenance and longevity

A well-laid patio needs little maintenance: sweep regularly, wash down seasonally, and pull weeds before they root deeply in joints. Pressure washing is effective but can damage jointing sand and soft stone if the pressure is too high, so use a fan nozzle and keep the lance moving. Re-sand joints after washing, and re-seal every few years if you sealed originally. With a proper base and occasional care, a concrete or stone patio should last decades, which makes the upfront effort of correct counting and base preparation well worth it.

• Area divided by paver area gives the base count.
• Add 5 percent waste for running bond, 10 percent for herringbone.
• Add more for curves, steps, and drains.
• Round up to the supplier's pack size.
• Keep spares for future repairs.

Counting pavers is simple arithmetic, but doing it before you order, with waste included, is what separates a smooth project from a stalled one. Measure your patio, choose your paver and pattern, and use the calculator above to get a count you can order with confidence.