How Much Sand for Pavers?

The number, and the number that matters more

A 20 × 12 ft patio — 240 sq ft — at the correct 1 inch bedding depth needs 0.74 cubic yards. About 1 ton, or 20 cubic feet bagged.

The figure worth memorising:

One cubic yard covers exactly 324 sq ft at one inch.

Not approximately. 27 cubic feet ÷ one twelfth of a foot = 324. It makes checking a supplier's quote a five-second job.

One inch. That's the whole rule.

Not two. Not three. Not "however much it takes to level it out."

This single decision separates a patio that stays flat from one that ruts and dips within a season, and getting it wrong is the commonest mistake in the entire job.

The calculator deliberately shows extra sand above 1 inch as its own output. The correct value for that figure is zero, and it reads zero at the defaults on purpose.

Why thicker is worse — which is genuinely backwards

More sand feels like more cushioning, better levelling, more forgiveness. It's the opposite.

Bedding sand is a setting layer, not a levelling layer. Its job is to let each paver seat itself evenly onto a base that is already flat.

And sand cannot be compacted into a stable structure the way graded aggregate can. So the more of it you have, the more there is to migrate sideways under load.

A 3-inch sand bed will move under:

• a wheelbarrow
• the legs of garden furniture
• anyone who stands in the same spot regularly

Every dip you've ever seen in a paved patio started exactly like that.

"But my base is uneven"

Then fix the base.

The levelling belongs in the compacted aggregate underneath — screeded and plate-compacted flat before any sand appears.

Using extra sand to hide a bad base doesn't fix the base. It delays the evidence until the first winter, at which point the repair involves lifting the pavers you just spent a weekend laying.

If the base isn't flat, the honest move is to go back to it. It's a miserable answer and it's the right one.

Use the right sand

Coarse, sharp, angular concrete or masonry sand.

The angularity is the entire point — the grains lock against one another and hold a paver still.

Fine, rounded play sand and soft builder's sand do not lock. They hold water and let pavers wander.

These are not interchangeable, and the bags don't always make the difference obvious. Read past the word "sand" on the label to what the grade actually is.

Order by volume, not by weight

Sand sold by weight is almost never bone dry, and moisture is exactly what varies.

Concrete sand runs roughly 2,600–2,900 lb per cubic yard depending on how wet it is — a spread of more than 10%. That's why your calculation and a supplier's tonnage will rarely agree precisely, and why density is an input here rather than a constant baked into the maths.

If you must order by weight, ask the supplier what their material actually weighs rather than using a figure off the internet. Including this one.

The calculator gives you the figure in tons alongside the cubic yards for exactly that conversation — 0.74 cubic yards comes out at almost exactly 1 ton at 2,700 lb/yd³, and you can watch that number move as you change the density.

Joint sand is a different product

The sand swept into the gaps between pavers once they're down — fine-graded or polymeric — is not what this calculator covers.

It depends on your joint width and paver size rather than the patio area, so it doesn't scale the same way at all.

Buy it separately, and don't be tempted to use the coarse bedding sand for it: the grains are too large to fill the joints properly and it'll keep washing out every time it rains.

Screed it, then stay off it

Once the sand is screeded flat, a single footprint is a dip — and a dip with a paver laid over it stays for the life of the patio.

• Work from the pavers you've already laid, never step onto the bed
• Screed only as far ahead as you can reach
• Don't tamp the sand down. Compaction happens at the end, through the pavers, with a plate compactor and a protective pad

That last one surprises people. The instinct to firm the bed up before laying is exactly wrong — the pavers are what transmits the compaction, and doing it beforehand just gives you a hard uneven surface to fight.