One of the most common questions we get before delivering aggregate in the Treasure Valley is: "How do I know how much to order?" Order too little and you're paying for a second delivery. Order too much and you're left with a pile on your driveway that your neighbor will inherit. This guide gives you the exact formula, a coverage table for common depths, and everything else you need to get the number right the first time.
Gravel — along with topsoil, sand, pea gravel, road mix, and most other aggregates — is sold by the cubic yard. One cubic yard is a cube that's 3 feet on every side: 3 ft × 3 ft × 3 ft = 27 cubic feet. Everything you order from us is priced and delivered by the yard.
That's really all there is to it. Measure your area in feet, pick a depth, and divide by 27. The tricky part is usually the depth — different materials and different applications call for different depths, and we cover that below.
Say your driveway is 60 feet long and 12 feet wide, and you want to put down 4 inches of road mix as a base layer. Here's the math:
Round up to 9 yards, then add about 10–15% for waste and settling (more on that below), and you're looking at ordering 10 yards for that driveway.
Use our material calculator on the delivery page to get an instant estimate — just enter your dimensions and depth. It automatically adds a 10% waste buffer.
Don't order exactly what the math says. Real-world projects always eat a bit more material than the formula suggests, for a few reasons:
Our standard recommendation: add 10% to your calculated number for a normal project. For areas with significant grade changes, soft soil, or drainage issues, bump that up to 15%. It's almost always cheaper to order slightly more in one delivery than to pay for a second trip.
This is where people get tripped up. How deep you go depends entirely on what you're using the gravel for. Here's a practical breakdown:
| Application | Recommended Depth | Notes |
|---|---|---|
| New gravel driveway | 4–6 inches | Use road mix or crushed aggregate. Layer in 2–3 in lifts and compact each one. |
| Driveway refresh/top coat | 2–3 inches | Adding to an existing base. Helps fill ruts and refresh surface. |
| Base for pavers / patio | 4 inches | Must be compacted firmly. Use road base or crushed rock, not pea gravel. |
| Base for outdoor tile | 3–4 inches | Compacted gravel base under a concrete bed or directly under thick tile. |
| Parking area | 4–6 inches | Go deeper (6 in) for heavy vehicle traffic. |
| RV or trailer pad | 6–8 inches | Heavy weight calls for a deeper, well-compacted base. |
| Pathway / walkway | 3–4 inches | Pea gravel or smaller crushed rock works well for foot traffic. |
| Drainage / dry creek bed | 4–6 inches | Use drain rock or washed chips. Depth depends on drainage volume. |
| Landscape decorative | 2–3 inches | Around shrubs, beds, or trees. Enough to suppress weeds. |
| Play area under equipment | 6–9 inches | Safety standard for fall zones. Pea gravel preferred. |
Another way to think about it: how much area does one cubic yard cover at different depths? This table makes it easy to work backwards from your square footage.
| Depth | Coverage per Cubic Yard | Cubic Yards per 1,000 sq ft |
|---|---|---|
| 1 inch | 324 sq ft | 3.1 yards |
| 2 inches | 162 sq ft | 6.2 yards |
| 3 inches | 108 sq ft | 9.3 yards |
| 4 inches | 81 sq ft | 12.3 yards |
| 5 inches | 65 sq ft | 15.4 yards |
| 6 inches | 54 sq ft | 18.5 yards |
| 8 inches | 40.5 sq ft | 24.7 yards |
| 12 inches | 27 sq ft | 37 yards |
So if you have a 500 sq ft patio area and need 4 inches of base gravel, you'd need about 500 ÷ 81 = 6.2 cubic yards. Order 7 to account for waste.
Most projects aren't perfect rectangles. Here's how to handle the common ones:
Break the shape into two rectangles. Calculate the cubic yards for each rectangle separately, then add them together.
For a circle: Area = π × radius². So a 20-foot diameter circle has a radius of 10 feet. Area = 3.14159 × 100 = 314 sq ft. Apply your depth and divide by 27 as usual.
Sketch the shape on paper and break it into rectangles and triangles. For a triangle, area = ½ × base × height. Add them all up. It doesn't need to be perfect — that's what the 10–15% buffer is for.
Measure the centerline length of the driveway, then multiply by the average width. For gentle curves, this gets you close enough. For switchbacks or dramatic bends, break it into straight segments.
We deliver road mix, pea gravel, drain rock, washed rock, sand, and topsoil throughout the Treasure Valley. No minimum order, same-week delivery available.
Sometimes gravel is quoted in tons rather than cubic yards. The conversion depends on the material's density:
| Material | Approx. Weight per Cubic Yard | Yards per Ton |
|---|---|---|
| Road Mix / Crushed Base | 1.5–1.7 tons | ~0.6–0.7 yds/ton |
| Pea Gravel | 1.4–1.5 tons | ~0.67–0.7 yds/ton |
| Drain Rock / Chips | 1.35–1.5 tons | ~0.67–0.74 yds/ton |
| Sand (dry) | 1.3–1.4 tons | ~0.71–0.77 yds/ton |
| Topsoil | 1.0–1.2 tons | ~0.83–1.0 yds/ton |
We quote and deliver by the cubic yard, so you'll always know exactly what you're getting. If you get a quote in tons from another supplier, just use the conversions above to compare apples to apples.
Material costs in the Boise area (Meridian, Nampa, Eagle, Star, Middleton, Kuna) generally run in these ranges. Note that prices vary by supplier and can shift with fuel and material costs:
Our current pricing is listed on the material delivery page. We're transparent about it — you'll see the price before you book, and it won't change after delivery.
The formula above works for most straightforward projects. But sometimes it makes more sense to just describe the job and get a recommendation:
Give us a call or text at (208) 906-3838 and describe what you're doing. We can usually help you nail down the right amount and the right material in a few minutes.
Dynamo Hauling delivers aggregate throughout the Boise metro: Boise, Meridian, Nampa, Eagle, Star, Middleton, Kuna, Garden City, and surrounding areas. We deliver road mix, pea gravel, drain rock, washed rock, sand, and topsoil. Book online anytime and we'll confirm a delivery window.
Not sure what material you need? Check out our guide to Road Mix vs. Gravel vs. Pea Gravel to pick the right aggregate for your project.
We deliver aggregate throughout the Treasure Valley. Book online, we'll confirm same-day.
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