Clean stone or compactable base?
The stone grade affects both the job and the weight estimate. The names on a quarry’s price sheet can differ by region. Check local trade names and ask for a gradation sheet if the material has to meet a project specification.
| Material | What to ask for | Typical use | Calculator assumption |
|---|---|---|---|
| #57 clean stone | Coarse, low-fines gradation; confirm whether it is washed | Drainage aggregate and some surface layers | 1.35 short tons/yd³ |
| Crusher run / dense-graded base | Top size and amount of fines; “#411” varies by market | Compacted driveway or patio base | 1.45 short tons/yd³ |
| #4 clean stone | Coarse gradation, roughly 2 in. down to 3/4 in.; confirm local product | Coarse drainage or stabilization layer where specified | 1.45 short tons/yd³ |
| #1 large stone | Large gradation, roughly 3½ in. down to 1½ in. | Deep stabilization or coarse fill where specified | 1.50 short tons/yd³ |
Grade numbers describe particle size ranges, not density or guaranteed performance. ASTM D448 classifies standard aggregate sizes; project requirements and local quarry products still control. If the quarry names the parent rock, compare its trap rock and crushed granite products by grade and loose weight. Larger erosion armor is a separate selection: use the riprap calculator for that work.
Worked example: 40 × 12 ft at 4 in.
- Area: 40 × 12 = 480 sq ft.
- Installed volume: 480 × 4 ÷ 324 = 5.93 yd³.
- With 10% added: 5.93 × 1.10 = 6.52 yd³.
- Estimated #57 weight: 6.52 × 1.35 = 8.80 US short tons.
If the area is irregular, divide it into rectangles, total their square footage and enter an equivalent length and width. The yardage calculator rounds volume to your supplier's selling step and checks delivery capacity. The tons calculator estimates quarry weight; the bag calculator counts packages from their labeled volume.
Five details worth confirming
- Finished depth: measure low spots as well as the average layer.
- Grade: describe the use, then confirm top size and fines with the yard.
- Loose bulk density: request the supplier’s tons per cubic yard for this material.
- Allowance: cover uneven ground, spillage or a known compaction factor without counting one issue twice.
- Delivery: ask the hauler about payload, gate width, overhead clearance and where the pile can be tipped.
For a base on soft ground, stone volume alone does not solve a weak subgrade. See how to address rock sinking into soil. For a drainage project, compare drain rock and plan a suitable outlet.
Why the delivered weight can differ
These preset densities are planning assumptions. Rock type, particle shape, gradation, stockpile moisture and how a load is measured all change the tons in a cubic yard. ASTM C29/C29M measures aggregate bulk density under defined loose or compacted test conditions; it does not make one conversion factor universal. A Penn State road materials calculator likewise separates finished depth from loose delivered quantity and permits a custom density and compaction ratio.
Drainage and bearing behavior also depend on the complete gradation and layer design. FHWA guidance notes that gradation changes a granular base’s stability and permeability. Clean crushed stone can form an open drainage layer, while a dense blend with suitable fines is used for stable compacted bases. A clean-stone layer still needs a compatible separator and a route for water to leave; FHWA’s drainage guidance explains why fines entering that layer matter.
Crushed stone questions
How much crushed stone do I need for 100 square feet at 3 inches deep?
The installed volume is 100 × 3 ÷ 324 = 0.93 cubic yard. At the calculator's 1.35 US short tons per cubic yard planning density, that is about 1.25 tons before any allowance, or 1.38 tons with 10% added. Your supplier’s actual density may differ.
Is #57 stone the same as crusher run?
No. #57 is a coarse gradation usually supplied with little fine material; crusher run is a dense blend of stone and fines designed to compact as a base. “#411” is a regional trade name for some dense-graded products. Ask your supplier for its gradation rather than ordering by name alone.
Should I add 10% for compaction?
Ten percent is only a planning allowance, not a universal compaction factor. Whether extra material is needed depends on the aggregate, whether your depth is loose or finished, the subgrade and placement method. If your supplier provides a loose-to-compacted factor, use that information and avoid adding the same allowance twice.
Can the calculator verify the weight on a delivery ticket?
No. It estimates tons from dimensions and an assumed loose bulk density. A quarry scale ticket records the actual delivered weight. For a disputed load, compare the ticket and the ordered tonnage; a photo of the pile cannot establish its weight reliably.