[stonecalc id=”road-base”]
Road Base Calculator Guide
A farm lane or private road is a driveway at scale, and scale changes the game: hundreds of feet of length turn every inch of depth into truckloads. At 8 inches deep, a 12-foot-wide lane consumes roughly 46 tons of crusher run per 100 feet — so a quarter-mile drive is a 600-ton project. This calculator does that multiplication honestly, at 1.55 tons per cubic yard with a 15% compaction allowance.
Because tonnage is so sensitive to depth, resist the temptation to shave an inch to save money. An under-built lane fails in the wheel tracks within a wet season, and rebuilding costs more than building right once.
How Many Tons of Road Base Does 100 Feet of Lane Take?
| Lane width | Depth | Per 100 ft (yd³) | Per 100 ft (tons) |
|---|---|---|---|
| 10 ft | 6 in | 18.5 | 28.7 |
| 10 ft | 8 in | 24.7 | 38.3 |
| 12 ft | 8 in | 29.6 | 45.9 |
| 12 ft | 10 in | 37.0 | 57.4 |
Six inches suits car-only lanes on firm ground; 8 inches is the sensible default where pickups, deliveries, and tractors run; 10 or more belongs on soft subgrade or routes that see loaded trucks. Figures are before the 15% allowance the calculator adds.
Lifts, Fabric, and Crown — the Three Rules of Lane Building
- Geotextile first on soft ground. A woven stabilization fabric between subgrade and stone stops the base from punching into mud — on wet clay it can save 2–3 inches of stone across the whole lane, which pays for the fabric several times over.
- Build in 3–4 inch lifts. Compaction equipment only densifies the top few inches, so an 8-inch base goes down as two compacted lifts, never one loose dump.
- Crown 2–4%. Shape the centerline a quarter to a half inch higher per foot of half-width so water runs off sideways. Standing water is the origin story of every pothole.
Maintain the lane by re-grading annually and keeping ditches open at the edges; drainage does more for longevity than fresh stone does. For material specifics on the default base grade, see the crusher run calculator, and to price the whole tonnage before committing, run it through the gravel driveway cost calculator.
[stonecalc_faq id=”road-base”]