Know what your paver patio needs before you buy

It depends on the size, and on the joint. A 4 by 8 in paver covers 32 square inches, so 4.5 fit in a square foot laid tight, and about 4.3 once you allow an eighth of an inch joint. A 12 by 12 gives roughly one per square foot, a 6 by 6 about four, and a 24 by 24 one every four square feet. The figure for your exact size and joint is shown in the results above. Order the cut allowance on top of it, because an offcut from one edge almost never fits another.

Four to six inches compacted for a patio or path, eight to twelve for a driveway. The part that catches people out is that gravel is sold loose and compacts about twenty percent under a plate. If you want four inches in the ground, ordering exactly four inches worth leaves you with about three and a quarter and a second trip to the yard. This calculator orders the loose volume and shows you both figures, so you can see what you are paying for and what you end up with.

Two different products doing two different jobs, and mixing them up is the most common paver mistake there is. Bedding sand is coarse concrete sand, screeded about an inch deep under the pavers to set them level. Jointing sand, usually polymeric, is swept into the gaps between the pavers at the very end, then wetted so it sets and locks everything together. Bedding sand in the joints washes out and grows weeds. Polymeric sand under the pavers sets into a hard, uneven layer you cannot screed. Buy both, and keep them apart.

Five percent covers a plain rectangle laid in stack bond with no border. Ten is the sensible default for most patios. Go to fifteen for herringbone, which meets every edge at forty five degrees and turns the whole perimeter into cuts, and for any layout with curves, circles or a contrasting border course. Add more again if you are new to a masonry saw, because the first few cuts of the day are rarely the ones you keep.

Four things, in order of how expensive they are to fix. Skimping on the base, which is invisible for one season and then shows up as ruts and rocking pavers. Compacting the base in one thick lift instead of two or three inch layers, which leaves it soft in the middle. Using too much bedding sand to make up for an uneven base, which ruts under load. And leaving out the edge restraint, which is the cheapest item on the list and the one holding everything else in place. Nothing on the surface can rescue a bad base, so spend the effort down there.