Quick Verdict
To figure out how much gravel you need in Oregon, the math is simple: length times width times depth (all in feet) divided by 27 gives you cubic yards. Then add roughly 10 to 15 percent overage because spreading and compacting loses depth, and convert yards to tons if your supplier sells by weight. Rural Oregon sites also have to clear delivery minimums. Get the depth right for the use, do the math, add overage, and order a little extra so you do not run short partway through.
The Basic Volume Formula
Gravel is sold by volume (cubic yards) or weight (tons), so the first job is finding the cubic yards. The formula:
Length (ft) x Width (ft) x Depth (ft) / 27 = cubic yards
The 27 converts cubic feet to cubic yards, since one cubic yard is 27 cubic feet. The only trick is putting depth in feet: 4 inches is 0.33 feet, 6 inches is 0.5 feet. For the broader picture of materials and hauling, see our excavation materials and hauling guide.
Step One: Measure the Area
Measure the length and width of the area you are graveling, in feet. For a rectangle, that is straightforward. For an irregular shape, break it into rectangles, calculate each, and add them up.
- Driveway: measure length and average width.
- Pad or parking area: length by width.
- Path: length by width (paths are narrow, so width matters).
Write the numbers down; you will use them in the math.
Step Two: Pick the Depth by Use
Depth depends on what the gravel is for. Deeper for heavier use, shallower for light surfaces.
| Use | Typical Depth | In Feet |
|---|---|---|
| Light path / topdressing | about 2 inches | 0.17 |
| Walkway / patio base | about 3-4 inches | 0.25-0.33 |
| Residential driveway surface | about 4 inches | 0.33 |
| Driveway base over soft ground | 6 inches or more | 0.5+ |
Step Three: Do the Math
Plug your numbers in. A worked driveway example:
- Driveway: 40 ft long, 12 ft wide, 4 inches (0.33 ft) deep.
- 40 x 12 x 0.33 = about 158 cubic feet.
- 158 / 27 = about 5.9 cubic yards.
A pad example:
- Pad: 20 ft x 20 ft, 6 inches (0.5 ft) deep.
- 20 x 20 x 0.5 = 200 cubic feet.
- 200 / 27 = about 7.4 cubic yards.
That is the base quantity before overage. For more worked examples across project types, see our how to estimate material quantity article.
Step Four: Add Overage for Compaction
Loose gravel loses depth when it is spread and compacted, and you also lose a little to spillage and uneven subgrade. So you order extra, typically about 10 to 15 percent.
- Driveway example: 5.9 yards x 1.12 = about 6.6 yards, round up to 7.
- Pad example: 7.4 yards x 1.12 = about 8.3 yards, round up to 9.
Ordering a little extra is cheaper than coming up short and paying a second delivery and minimum. On Oregon base work, where compaction is significant, the higher end of the overage range is wise.
Step Five: Convert Yards to Tons
Many suppliers sell crushed rock by the ton, not the yard. You convert using the material's weight per cubic yard, which varies by rock type and moisture. Crushed rock is heavy, so a cubic yard is well over a ton.
Because the conversion factor depends on the specific product, confirm it with your supplier. Our cubic yard to ton conversion for gravel article walks through it. The point is to order the right tonnage so you do not under- or over-buy.
Oregon Ordering Realities
A few local factors affect what you actually order.
- Order extra for compaction. Spreading and compacting valley base loses depth, so the overage matters more here.
- Delivery minimums. Rural Oregon sites often have minimum loads or delivery charges, so very small orders may cost more per yard.
- Haul distance drives price. The further from the pit, the higher the delivered cost, regardless of quantity.
What Gravel Costs in Oregon
Material cost is per yard or ton, plus delivery. These are baseline ranges, not fixed prices.
| Driver | Baseline Range |
|---|---|
| Crushed gravel, delivered, per cu yd | $45 - $110+ per cu yd |
| Fill / pit run, delivered, per cu yd | $20 - $75+ per cu yd |
| Mobilization / delivery | $250 - $800+ flat |
| Minimum job callout (small residential) | $500 - $1,500+ |
Industry Baseline Range: a small driveway order of about 7 yards of crushed rock falls within the per-yard range above plus delivery, so the total scales with quantity, product, and haul distance.
These are industry baseline ranges for planning only -- actual pricing depends on site conditions, soil, access, depth, haul-off, and current market conditions. Get a site-specific quote.
Current Market Reality
Real costs often run 2 to 3 times a bare material estimate once a long quarry haul, delivery minimums, the deeper base wet clay demands, and the spreading and compacting labor are added in. The gravel itself is only part of the bill.
A Quick Recap
- Measure the area in feet.
- Pick the depth by use, and put it in feet.
- Length x width x depth / 27 = cubic yards.
- Add 10 to 15 percent overage.
- Convert to tons if ordering by weight, and check delivery minimums.
The Bottom Line
Figuring out how much gravel you need is simple arithmetic plus an overage cushion: measure, pick a depth, divide by 27, add 10 to 15 percent, and convert to tons. On Oregon's soft ground, lean toward the higher depth and overage. Our excavation services crew calculates quantities and places the rock for your project. To get a materials plan and quote, request a free estimate.