Boneyard Tools

Paver Base and Bedding Sand Guide

The layers under a lasting patio, why bedding sand and jointing sand differ, and how to order pavers with the right waste allowance.

The layers that make a patio last

A durable paver patio is built in layers, and the pavers are only the visible top. Beneath them sits a thin, screeded bed of coarse bedding sand, usually about one inch deep, that lets each paver settle into an even plane. Under that is the workhorse: a compacted gravel or crushed stone base, typically four to six inches thick, that carries the load and drains water away. Below everything is firm, compacted subgrade soil. This calculator sizes the bedding sand and the pavers themselves, so plan the gravel base separately once you know your soil and drainage.

Bedding sand versus jointing sand

Two different sands do two different jobs, and confusing them causes problems. Bedding sand is the coarse layer you screed flat and set pavers into, and it is what the cubic yard figure here estimates. Jointing sand, often a polymeric sand, is swept into the narrow gaps between pavers after they are laid, then wetted so it hardens and locks the field together. You cannot substitute one for the other: fine jointing sand makes a poor unstable bed, and coarse bedding sand will not knit the joints. Order both, sized for their own tasks.

Choosing a waste allowance for your pattern

Waste is the extra material you buy to cover cuts, breakage and mistakes, and the right amount depends on your layout. A simple running bond or stack grid wastes little, so ten percent is usually plenty. Diagonal, herringbone and basketweave patterns force many angled cuts around the perimeter, so fifteen to twenty percent is safer. Curves, circles and borders waste the most of all. The calculator applies your chosen percent before rounding up to whole pavers, so raising the waste for a busy pattern directly raises the count it tells you to buy.

Ordering pavers you can match later

Pavers are made in batches, and color and dimension can shift subtly from one production run to the next. That is why buying tight to the exact count is a false economy. Order your full waste allowance and set aside a small stack of leftovers from the same delivery. Years later, when a paver cracks or a tree root lifts a corner, those matched spares let you make an invisible repair instead of hunting for a discontinued color. Store them somewhere dry and out of direct sun so they weather at a similar pace to the patio.

Frequently asked questions

How thick should the gravel base be?

Four inches suits foot traffic on well-drained soil, while six inches or more is wise for clay, poor drainage, or anything a vehicle will cross. This tool does not size the gravel, so estimate it separately from the base depth your site needs.

Can I skip the sand and lay pavers on gravel?

Not for a smooth, lasting finish. The bedding sand is what lets each paver seat level and stay put. Laying straight on gravel leaves an uneven surface that shifts and rocks underfoot over time.