#2 Stone

Number 2 stone comes from crushing quarried rock, most often limestone, traprock, or granite, and screening it to the ASTM D448 No. 2 gradation band, roughly 1.5 to 2.5 inches. Unlike dense graded products such as crusher run, it is single sized and screened to remove fines, which is what gives it its open, high void structure. That screening step is also why color and exact weight per yard vary by region, since it depends entirely on the parent rock at the quarry supplying a given area. Because there is so little dust or fine material mixed in, number 2 stone will never pack down into a hard, walkable crust the way a fines heavy base material does. Its angular, freshly crushed faces are what let individual pieces lock against each other for stability, but that same angularity makes it uncomfortable to walk on directly and rough on tires if used as a final wearing surface instead of a base or fill layer.

Start by grading and compacting the subgrade so the stone sits on a firm, even surface rather than bridging over soft pockets unevenly. For drainage, driveway sub base, and any application meant to last more than a season, lay landscape fabric or geotextile first. This one step matters more with number 2 stone than with finer materials, since its large voids are exactly what allows soil fines to migrate upward over a few years and choke off drainage or destabilize the base. Spread the stone in a lift of at least 3 to 4 inches, since thinner layers meant for pea gravel or mulch will not lie flat or perform correctly at this particle size. If it will carry a topping layer, keep that top course thinner and more compactable, such as 57 stone, so the finished surface is walkable while the number 2 layer underneath keeps handling drainage and load distribution.

Compared with 57 stone. Number 57 stone, at about three quarters of an inch, is smaller, drains fast, and is comfortable enough underfoot to serve as a driveway topping or concrete aggregate. Number 2 stone is noticeably coarser and better suited to base lifts, culverts, and construction entrances where mass and resistance to displacement matter more than a finished, walkable surface.

Compared with crusher run. Crusher run is dense graded with fines mixed in, so it compacts into a hard, driveable surface but drains poorly and puddles. Number 2 stone is single sized with almost no fines, so it drains excellently and resists washing away, but it will never compact into a solid crust the way crusher run does.

How much number 2 stone do I need. Multiply area in square feet by depth in feet, then divide by 27 to get cubic yards. As a shortcut, one cubic yard covers about 108 square feet at a 3 inch depth or 81 square feet at 4 inches, the typical depth range for this stone. Do not use thinner coverage numbers borrowed from pea gravel or mulch, since particles this large need real depth to lie flat and function.

How it is sold and delivered. Number 2 stone is sold and delivered in bulk by the cubic yard or by the ton, with roughly 1.4 to 1.5 tons per cubic yard as a planning estimate. Ton based ordering is common on larger commercial or DOT spec jobs, while cubic yards are easier for smaller residential projects like driveway base or drainage work. Confirm actual tonnage against a scale ticket for large orders, since density shifts with parent rock and moisture.