How Much Gravel for a 16x20 Patio?
A 16 by 20 foot patio is 320 square feet. How much gravel for a 16x20 patio depends on depth: at 3 inches it is about 2.96 cubic yards or 4.1 tons. Suppliers usually sell by the ton, so the tonnage is the number to give them.
Volume and tonnage calculator →The math for a 16x20 patio
- Area: 16 × 20 = 320 sq ft.
- Depth in feet: 3 ÷ 12 = 0.250 ft.
- Cubic feet: 320 × 0.250 = 80.0 cu ft.
- Cubic yards: ÷ 27 = 2.96 yd³.
- Tons: × 1.4 = 4.1 tons.
The volume and tonnage calculator does this for any size.
Gravel needed by depth
| Depth | Cubic yards | Tons (approx.) | Tons +10% |
|---|---|---|---|
| 2 in | 1.98 | 2.8 | 3.0 |
| 3 in | 2.96 | 4.1 | 4.6 |
| 4 in | 3.95 | 5.5 | 6.1 |
| 6 in | 5.93 | 8.3 | 9.1 |
About gravel
Because ’gravel’ covers so many products, the weight per yard moves with stone size and how much fine material is in the pile. Rounded stone with no fines rolls under tires; crushed stone with fines locks together. Ask your supplier for their own tons-per-yard figure, since stone source and moisture shift it.
Preparing the patio
Remove sod, level the area with a slight slope away from the house, and lay landscape fabric if weeds are a concern. Edging keeps loose material inside the patio footprint. Since the patio carries foot traffic and furniture, a little extra depth is cheap insurance.
Ordering tips
- Round up. Compaction and uneven ground eat material. Adding about 10 percent is common.
- Delivery size. 4.6 tons fits in a single typical dump truck load; small loads may carry a delivery fee. See how many tons of gravel in a dump truck.
- Bulk vs bags. At this size bulk delivery is usually the practical choice.
- Where it drops. Have the truck dump as close to the patio as firm ground allows.
When to choose gravel
Works well for:
- Rural driveways and lanes where low upfront cost matters
- Drainage areas and around downspouts
- Temporary access while a site is under construction
Think twice for:
- Steep slopes, where loose stone washes downhill
- Spots plowed often, since plows push gravel into the lawn
- Areas next to doors, because stone tracks inside
Quick reference numbers
- Per inch over 100 sq ft: about 0.43 tons of gravel (0.31 cubic yards).
- Per inch over 1,000 sq ft: about 4.3 tons.
- Another size for comparison: a 12x24 area at 2 inches takes about 2.5 tons.
- Weight used here: about 1.4 tons per cubic yard.
Common estimating mistakes
- Ignoring the base. A thin surface layer over soft soil fails early no matter how much material is on top.
- Forgetting that compaction shrinks loose material. A loose 4-inch spread of a dense-graded stone may finish closer to 3 inches after rolling.
- Measuring only the main rectangle. Aprons, turnouts and curved edges add real square footage.
- Ordering exactly the math. Uneven ground and spillage nearly always need a little more than the flat calculation.
Questions people ask
How many tons of gravel for a 16x20 patio?
About 4.1 tons at 3 inches deep, or 4.6 tons with 10 percent extra.
How many cubic yards is a 16x20 patio at 3 inches?
About 2.96 cubic yards.
How much does a cubic yard of gravel weigh?
Usually around 1.3 to 1.5 tons, depending on stone size, fines and moisture.
How deep should gravel be for a patio?
The table above shows 2 to 6 inches. Shallower depths suit top dressing; deeper depths suit new installs and heavier use.
How many square feet is 16x20?
320 square feet.
Related guides
- How Much Does a Ton of Gravel Cover? Depth Chart
- Tons to Cubic Yards for Gravel: Conversion Chart
- How Many Tons of Gravel in a Dump Truck? Loads and Coverage
- How Much Gravel for a 16x16 Patio?
- How Much Gravel for a 16x18 Patio?
As an Amazon Associate, AsphaltTons.com earns from qualifying purchases. Product links below are sponsored.