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Gravel for circular, curved, and irregular driveways, including turnarounds and parking spurs.
With these inputs:
| Result | Value |
|---|---|
| Gravel needed | 92.15 tons |
| Volume | 61.44 yd³ |
| Total paved area | 2,262 sq ft |
| Estimated cost | $2,747 – $4,406 |
| Shape | Circular loop, 30 ft radius |
| Centreline length | 188 ft |
| Width | 12 ft |
| Driving surface area | 2,262 sq ft |
| Turnaround area | — |
| Total area | 2,262 sq ft |
| Depth | 8 in |
| Volume | 61.44 yd³ |
| Weight | 92.15 tons |
| Truck loads | 8 × 12 tons |
Measuring along the centreline is what makes a curved estimate accurate — measuring the outside edge overstates the area, and the inside edge understates it. A loop driveway needs at least a 28 ft inner turning radius for most vehicles.
Curved driveways are hard to estimate because the area is not a simple rectangle. This calculator handles a circular loop by its centreline and width, and lets you add a turnaround or parking spur, so the quantity reflects the shape you are actually building.
Measure the length along the centreline of the curve, not the inside or outside edge, then multiply by the width. That gives the true surface area for any curve.
A minimum centreline radius of about 28 to 30 feet, so standard vehicles can navigate the loop without a three-point turn. Tighter loops need a wider driving surface to compensate.
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