Sand Calculator

The Sand Calculator asks for the sand class up front because price, density, and end-use suitability all swing on it. A 5-ton load of fill sand and a 5-ton load of kiln-dried play sand cover the same area at the same depth, but cost two to four times different and behave nothing alike under foot traffic, mortar mixers, or paver edging.

Play sand is washed, kiln-dried, and graded fine and uniform. The drying step pushes the price up — most bulk suppliers charge $25-$40 per ton compared to $10-$20 for unwashed fill — and the bagged retail product runs even higher, around $5-$7 per 50-lb bag. Play sand is the right pick for sandboxes, volleyball courts, indoor sand-art areas, and anywhere the sand needs to be dust-free and skin-safe. It is wrong for mortar (too fine, no sharp edges to bind) and wasteful under pavers (the price premium buys nothing structural).

Masonry sand is washed and graded to a tight specification (ASTM C144 in the US, BS EN 13139 in the UK) so it produces consistent mortar workability. The grading runs slightly coarser than play sand and the particles are angular rather than rounded — that angular shape is what gives mortar its bond strength. At $20-$35 per ton bulk, it is the right pick for brick and block mortar mixes and for paver bedding sand under tight-jointed pavers. Use it whenever a mortar mix calls for "sand" without further qualification.

Construction sand (sometimes called concrete sand or sharp sand) is the coarsest and densest of the four classes — particles up to about 4 mm across, with crushed-rock fines mixed in. The density runs roughly 1.45 tons per cubic yard, slightly heavier than masonry sand. It is the standard fine aggregate for poured concrete mixes, where the angular faces lock into the cement paste and produce stronger compressive strength than smoother sand would. At $15-$30 per ton it is also one of the cheaper bulk options, which makes it a popular substitute for fill sand on jobs that need a bit more compaction strength.

Fill sand is the cheapest bulk class — $10-$20 per ton — and the most variable in moisture content, fines, and grading. It is unwashed, often dredged or pit-run, and may carry organic matter, clay, or stones up to 1/4 inch. Fill sand is the right pick for non-structural backfill: filling around buried pipes, levelling a yard before topsoil, or backfilling a deep utility trench. It is wrong for mortar (organics weaken the bond), wrong for paver bedding (clay fines hold water and freeze-heave), and wrong for sandboxes (dirt content and unknown source).

Sand is sold by weight (tons or pounds) when bulk and by volume (cubic feet or 50-lb bags) when retail. The reference table below converts between the two for the four sand classes this calculator supports, at the standard 1.10 overage factor built into bulk orders.

The bag count is the same across all four because a 50-lb bag of any sand holds roughly 0.5 cu ft regardless of grading — the bag size is fixed, and the small density variations within a single class fall inside packaging tolerance. That means a cubic yard of any sand is roughly 54 retail bags, give or take 5%. Coverage drops in proportion to depth — doubling the depth halves the area one ton can cover.

Most homeowners over-order at bag-buying scale because they forget that a 50-lb bag covers only 0.5 cu ft. A 4×4 ft sandbox at 6 inches deep needs 8 cu ft, or 16 retail bags — easy to under-order if you eyeball the bags rather than measure.

The 10% overage built into the calculator covers two losses that almost always show up: spillage during transfer from the truck or wheelbarrow into the trench or sandbox, and settling once the sand is in place and gets walked on or rained on. For dry pickup orders where you load and unload the bags yourself, 5% overage is usually enough; for wet bulk drops that spread on uneven ground, 12-15% is realistic on the largest jobs.

Translating measurements into a clean material order takes five steps. Skipping any of them tends to produce either a half-load short delivery (most common) or a quarter-yard pile of leftover sand sitting on the lawn.

1. Measure length and width to the inside of the contained area. For a sandbox, that is inside the timber frame. For a paver patio, inside the perimeter restraint. For a drainage trench, the trench width at the bottom — not the surface width, which is wider on a sloped trench wall. Use a tape measure rather than a rangefinder; rangefinders introduce a 0.5-1% error at construction distances.

2. Set the depth with the application in mind. A play sandbox uses 8-12 inches so kids can dig without hitting the bottom. Paver bedding sand sits at exactly 1 inch over the compacted gravel base — thicker bedding lets pavers tilt and rock under load. Concrete subbase sand runs 2-4 inches under the slab to break capillary moisture and bring the form to grade. Drainage fill sand fills 6-12 inches around the perforated drain pipe.

3. Choose the sand class before pricing. Use the comparison section above. Pricing a project around fill sand and then upgrading to masonry sand mid-job typically doubles the per-ton cost — call the supplier with the right class identified, and confirm they can deliver that class from their stock (some yards carry only one or two of the four classes).

4. Order bulk above 2 cubic yards, retail below. The crossover point sits where the supplier delivery fee ($50-$150) absorbs the per-ton savings. A 1-yard order at $30/ton bulk is $40 of sand against a $100 delivery fee, while 12 retail bags from a home centre cover the same volume at $60-$84 — bags win by a wide margin on small jobs. Above 2 cu yd, bulk takes over and stays cheaper through the largest residential orders.

5. Spread in 2-inch lifts and screed level. Sand poured in a single deep lift compacts unevenly — the bottom is denser than the top, and the surface settles weeks later as the lower layer adjusts. Spread 2 inches at a time, walk it, water it lightly to settle the fines, and screed flat with a 2×4 dragged across guide rails before adding the next lift. This is especially important for paver bedding, where a 1/4-inch high spot becomes a paver tilt that will not screw flat regardless of how the next paver is laid. The same care matters when staging sand under a poured concrete slab — bring the sand to grade before the forms go in, not after.

Three mistakes account for almost every sand order that misses on price or quantity, and each is preventable with a five-minute call to the supplier before you place the order.

The first is substituting fill sand for masonry sand to save money. Fill sand carries organic matter, clay, and inconsistent grading — none of which matter when you are filling a utility trench, all of which matter inside a mortar mix or under tight-jointed pavers. Mortar mixed with fill sand cures weaker, sets slower, and develops surface efflorescence as the buried clay fines wick to the surface during the first wet-dry cycle. Paver bedding made of fill sand pumps water in heavy rain and spits up the joint sand within months. The $5-$15 per ton you save against masonry sand evaporates the first time the wall or patio needs repair — and the repair cost is structural, not just cosmetic.

The second is forgetting that polymeric sand is sold by the bag, not the cubic yard. Polymeric sand goes between the joints of an installed paver patio, not under the pavers as a bedding layer. It bonds with water activation and holds the joints against weeds and ant tunnels. A 50-lb bag covers 75-100 sq ft of standard 4×8 paver joints — radically different coverage from bulk bedding sand at the same weight. The calculator on this page sizes the bedding layer; for the joint-sand line item, plan separately at one bag per 75-100 sq ft of paver area depending on joint width. Mixing the two in a single order to a bulk supplier is a common point of confusion since suppliers often stock both products under the "sand" category.

The third is ordering wet bulk sand without checking moisture. Bulk sand sold from an outdoor stockpile after a rainy week can carry 5-10% extra weight in water — and you pay by the ton, including the water. A 5-ton order at 10% moisture is really 4.5 tons of dry sand and 0.5 tons of water, and the dry coverage drops accordingly. Reputable suppliers cover stockpiles with tarps and offer dry delivery from a covered shed for an extra $10-$20 per ton; on small orders that is rarely worth it, but on jobs over 5 tons it pays for itself. Always ask the supplier whether the stockpile was covered and when it was last replenished — fresh stockpile sand is consistently drier than aged outdoor stock.

A fourth mistake worth flagging on long projects is using construction sand under pavers when masonry sand is specified. The two look almost identical to a non-specialist eye, but construction sand is too coarse for tight-jointed paver bedding — the larger particles create high spots that lift individual pavers and make the surface uneven within a few months. The calculator treats them as different classes for a reason. If your supplier ships construction when you ordered masonry, send it back rather than using it as a substitute. The same care applies inside a poured concrete footing where the spec demands construction sand, not masonry — the angular grading and density both matter for compressive strength.