Types of Sand: Play vs Mason vs All-Purpose vs Concrete vs Polymeric

The short answer

Sandbox? Play sand. Mortar or pool base? Mason sand. General yard work? All-purpose. Mixing concrete? Concrete sand. Paver joints? Polymeric sand. The wrong sand doesn't just perform worse — fine sand in a concrete mix weakens it, and coarse sand in mortar makes it crumbly. Grain size is the whole game, and the table below matches each sand to its jobs.

The five sands, compared

Every bag or bulk load you'll find at a yard or home center is one of these five. Here's how they differ on grain, texture, and cleanliness:

Use this / not this, by project

Pick your project in the left column. The right column is what to avoid and why:

A note on bedding vs joint sand for pavers

Pavers use two different sands doing two different jobs: coarse concrete sand as the 1-inch bedding layer, and polymeric sand swept into the joints to lock the pavers together. Mixing them up is the most common paver-sand mistake. Our paver base, sand, and gravel guide covers the full layer-by-layer build with quantities.

Bag vs bulk: the price cliff

Sand is sold two ways and the price difference is brutal. A 50-pound bag holds about 0.5 cubic feet, so a cubic yard — 27 cubic feet — is about 54 bags. At roughly $5 a bag, that's ~$270 per yard in bags versus $20–50 per yard in bulk from a landscape supply yard, plus a $50–150 delivery fee.

The rule of thumb: bags win under ~2–3 bags (small repairs, a sandbox top-up, anywhere a truck can't reach). Bulk wins for everything else — the delivery fee amortizes fast. A pool base needing 3 yards is about $105 in bulk sand (see our pool base sand chart) versus ~$800 in bags. For weight-based pricing, sand runs about 2,700 pounds per yard — multiply your yards by 1.35 for tons.

ASTM specs, in plain English

Bulk sand from a real supplier is often graded to an ASTM standard — a published spec that guarantees grain size and cleanliness. Two matter for homeowners:

ASTM C144 — the masonry/mortar sand spec. It defines a fine, clean sand that mixes into workable mortar. If a yard sells “masonry sand,” it's graded to this (or close).
ASTM C33 — the concrete aggregate spec. It defines the coarse, washed fine aggregate that goes into concrete. “Washed concrete sand” or “C33 sand” is what you want for mixing or for paver bedding.

You don't need to memorize these — but when a supplier asks what spec you need, the names above get you exactly the right pile. (No ASTM number governs play sand; its “kid-safe” claim comes from washing and screening, not a construction standard.)

Where to buy each sand

Not every seller stocks every sand, and buying from the right place saves money. Home centers carry bagged play sand, all-purpose sand, and polymeric sand — convenient, but the worst per-yard price. Landscape supply yards sell bulk mason, concrete, and all-purpose sand by the cubic yard or ton — the right call for anything over a few bags, and their staff can usually tell you which pile matches your project. Masonry suppliers are the best source for true C144 mason sand and will deliver to job sites. Polymeric sand is a bagged product almost everywhere — buy it by the bag based on your joint volume (a 50-lb bag covers roughly 60–100 square feet of pavers, depending on joint width).

Can you mix sands?

Sometimes — but know what you're making. Blending mason sand into all-purpose sand for lawn leveling is fine. Never blend your way around a spec: mixing play sand into a concrete batch to “stretch” your concrete sand changes the aggregate grading and weakens the result, and adding all-purpose sand to mortar makes it unpredictable. When a job has a spec (C33, C144), buy the spec'd sand. When it doesn't — sandbox top-ups, leveling, general fill — blending what's on hand is harmless.

Silica dust: the one safety note

All natural sand contains crystalline silica; the risk is breathing the dust, not touching the sand. Cutting or dry-sweeping large amounts of sand — or working with polymeric sand on a windy day — calls for a dust mask (N95 or better) and keeping the material damp while you work. Play sand gets extra scrutiny here: reputable brands test and label it, so buy it bagged from a known manufacturer rather than scooping unknown bulk sand for a sandbox.

How much sand do you actually need?

Once you've picked the type, the quantity math is the same for all of them: (length × width × depth in feet) / 27 = cubic yards. A 10×10-foot sandbox at 6 inches deep is (10 × 10 × 0.5) / 27 = 1.85 cubic yards — order 2 yards, or about 100 fifty-pound bags of play sand. Our sand calculator runs this for any shape and converts to tons and bags automatically.

Storage and handling

Bulk sand arrives in a pile — tarp it if it'll sit more than a day or two, because wet sand weighs more (delivery drivers care) and saturated sand is miserable to spread. Keep polymeric sand completely dry until it's in the joints: once the binders activate with water, any damp bag starts setting in storage. And a practical note — a cubic yard of sand is about 1.35 tons, so don't have it dumped anywhere your driveway or lawn can't take the weight.

Common mistakes

One sand for everything. The all-purpose bag is tempting; it's wrong for mortar, concrete, and paver joints. Fine sand in concrete. Mason or play sand in a mix produces weak, crumbly concrete. Coarse sand in mortar. Concrete sand makes mortar that won't bond properly. Buying bags for a bulk job. Past ~3 yards, bagged sand costs multiples of bulk. Wet polymeric sand. Store it dry or it sets before you use it.

A quick buying checklist

Before you order, run through this: 1) Match the sand to the job using the table above — not whatever's cheapest. 2) Decide bags vs bulk at the 2–3 bag threshold. 3) For bulk, confirm the pile name with the yard (“washed concrete sand,” not just “sand”) and ask if it's graded to C33 or C144 when the job needs it. 4) Check delivery access and have a tarp ready. 5) For polymeric sand, buy from a single lot — color can vary between batches. Get those five right and the sand part of your project is the part you never think about again.