What is the difference between bedding sand and polymeric sand?

Bedding sand (sharp/concrete sand) is the coarser layer pavers are laid and levelled on. Polymeric sand is a finer jointing sand blended with a polymer binder that sets hard once watered in, locking pavers in place and resisting weeds and ant erosion in the joints. Plain sharp sand works for joints in light foot-traffic areas, but polymeric is the standard choice for driveways.

How thick should the bedding sand layer be?

Most paver installation guides call for a 2.5 cm (1 in) compacted bedding sand layer. Thinner risks an uneven surface, while a much thicker layer compacts unevenly under the pavers and can cause them to rock or settle.

What is jointing sand used for in block paving?

Jointing sand is swept into the gaps between laid pavers and vibrated down to lock the units together and stop them shifting sideways under load. It is a separate, finer product from the bedding sand the pavers are laid on, and most Australian suppliers sell the two as distinct products.

Jointing Sand Calculator | Bedding Sand for Block Paving

How Much Paver Sand Do You Need?

Paver sand covers two different jobs on the same project: a bedding layer the pavers are laid and levelled on, and joint sand that fills the gaps between them once they're set. Getting either quantity wrong usually means a mid-job supply run. This calculator works out both volumes -- plus the combined weight, bag count, and cost -- from your paved area, bedding depth, chosen sand type, and an optional joint-fill calculation.

How to Use the Paver Sand Calculator

Enter the length and width of the area you're paving.
Enter the bedding depth -- typically 2.5 cm (1 in) compacted -- and pick a sand type: sharp/bedding sand, polymeric jointing sand, or stone dust (limestone screenings).
Turn on joint fill if you need a separate joint-sand quantity, and enter the joint depth (roughly your paver's thickness) -- the calculator adds that volume to the bedding layer and returns total volume, weight, bag count, and estimated cost.

The Paver Sand Formula

Bedding volume = Area x bedding depth. When joint fill is included, joint volume = Area x joint-area fraction (the share of the paved surface that's open joint, typically 3-5%) x joint depth. The two volumes are added, a waste allowance applied, then multiplied by the sand's bulk density to get weight.

Worked example: a 5 m x 4 m patio (20 m²), 2.5 cm (0.025 m) bedding depth, sharp sand at 1,600 kg/m³, plus joint fill at a 4% joint-area fraction and 4 cm joint depth. Bedding volume = 20 x 0.025 = 0.5 m³. Joint volume = (20 x 0.04) x 0.04 = 0.032 m³. Total = 0.532 m³, or 0.585 m³ (about 0.77 cubic yards) with a 10% waste allowance. Weight = 0.585 x 1,600 ≈ 936 kg (0.94 tonnes) -- about 38 bags at 25 kg each.

Pro Tips

Worked cost example: for the 0.585 m³ (about 0.94 tonnes with a 10% waste allowance) patio example above, at a typical Australian price of around $65 per tonne, that's roughly 0.94 x $65 ≈ $61 in material cost, before delivery.

Bedding sand and jointing sand aren't interchangeable. Sharp/bedding sand is coarser and meant to be screeded flat and compacted under the pavers; polymeric jointing sand is finer, with a polymer binder that hardens once watered in, locking the joints against washout and weed growth -- worth the extra cost anywhere vehicles will drive over the joints.
Compact the bedding layer before laying pavers, not after -- screeding it flat and firm first stops the pavers settling unevenly once foot or vehicle traffic starts.