Tools · Base prep
Gravel compaction calculator: how many lifts, how deep to spread, how many tons
A base fails when it’s dumped in one thick layer and the compactor only packs the top. Enter the finished base depth and the machine you’re using, and get the number of lifts, how much loose stone to spread for each one, the grade marks and the tons to order.
With a plate compactor, keep each lift to 4 in. compacted or less. A 3,000 lbf rental plate handles about 3 in. of loose stone. Spread 2A about a third deeper than you want it finished: 8 in. loose packs to about 6 in. Plan on 2 to 2.16 tons per compacted cubic yard. Checked Nov. 13, 2026.
Base lift calculator
On the spec plate or in the rental listing. Typical forward plates run 3,000 to 5,000 lbf; reversible plates 7,000 and up.
| Tons of 2A to order2.0 to 2.16 tons per compacted yard | — |
| Compacted cubic yards | — |
| Loose cubic yardsWhat the truck delivers | — |
For dense-graded base like 2A, crusher run or modified stone. Clean stone such as #57 doesn’t pack the same way. Lift limits from Ohio DOT, CMHA and a plate compactor guide; loose ratio and tons from Penn State and Ohio DOT.
Lift limits by compactor
| Compactor | Max lift | Source |
|---|---|---|
| Forward plate, about 3,000 lbf | About 3 in. loose (about 2¼ in. compacted) | Plate compactor guide: 1 in. of material per 1,000 lb of force |
| Any plate compactor | 4 in. compacted | Ohio DOT 304 |
| Reversible plate, 7,000 lbf | 4 to 6 in. | CMHA PAV-TEC-002; thinner lifts for 5,000 lbf machines |
| Roller under 10 tons, or no vibratory roller | 4 in. compacted | Ohio DOT 304 |
| Vibratory roller, 10 to 12 tons | 6 in. compacted | Ohio DOT 304 |
| Vibratory roller over 12 tons | 8 in. compacted | Ohio DOT 304 |
The calculator uses the tighter of the plate rules: loose depth up to 1 in. per 1,000 lbf, never more than 4 in. compacted. When the base is deeper than one lift, it splits it into equal lifts, the way DOT specs require.
How it works
Lifts = compacted depth ÷ max compacted lift, rounded up. Each lift = depth ÷ lifts.
Loose depth = compacted depth × 1.33. Penn State’s DSA spec compacts 8 in. loose to 6 in., and 6 in. to 4½ in. (tech bulletin).
Compacted cubic yards = length × width × depth (in.) ÷ 12 ÷ 27.
Tons = compacted cubic yards × 2.0 to 2.16. Ohio DOT converts crushed stone base at 4,000 lb per compacted yard (Table 304.07-1); Penn State orders 0.04 tons per sq ft for 6 in. compacted, which is 2.16 tons per yard.
Get the base right
At least 4 in. compacted under patios and walks and 6 in. under residential driveways on well-drained soil. Go thicker for wet or weak soil and heavy freeze-thaw (CMHA).
At least 98% of standard Proctor for patios and residential driveways; 98% of modified Proctor for vehicle areas (CMHA).
Finished base within ±3/8 in. under a 10 ft straightedge, and each lift within +3/4 to −1/2 in. of plan (CMHA).
A handful of base should hold together when squeezed (plate compactor guide). Too dry and it won’t pack; add water and rework it.
Questions
How thick should each lift of gravel be?
It depends on the compactor. Ohio DOT caps lifts at 4 in. compacted for plate compactors and rollers under 10 tons, 6 in. for 10 to 12 ton vibratory rollers, and 8 in. over 12 tons. The hardscape industry’s guide calls for 4 to 6 in. lifts with a 7,000 lbf reversible plate and thinner lifts with a 5,000 lbf machine.
How much does gravel compact?
Dense-graded stone like 2A shrinks about a quarter in depth. Penn State’s Driving Surface Aggregate spec places 8 in. loose and compacts it to 6 in., or 6 in. loose to 4½ in. That’s a loose-to-compacted ratio of about 1.33.
How many tons of 2A for a 6 inch base?
About 2 to 2.16 tons per compacted cubic yard. Ohio DOT converts crushed stone base at 4,000 lb per compacted yard, and Penn State orders 0.04 tons per square foot for a 6 in. compacted layer, which works out to 2.16 tons a yard. A 12 × 20 ft patio base at 6 in. is about 4.4 compacted yards, or 8.9 to 9.6 tons.
How thick should a paver patio or driveway base be?
The Concrete Masonry and Hardscapes Association’s minimum is 4 in. after compaction for patios, walks and pedestrian areas and 6 in. for residential driveways, both on well-drained soil. It notes thicker bases are often used where there are many freeze-thaw cycles, and wet or weak soils need more.
How compact is compact enough?
For patios and residential driveways the hardscape guide calls for at least 98% of standard Proctor density, with the finished base within 3/8 in. under a 10 ft straightedge.
Sources: Concrete Masonry and Hardscapes Association, PAV-TEC-002-22, Construction of Interlocking Concrete Pavements (rev. 2022); Ohio DOT, Manual of Procedures, 304 Aggregate Base (lift limits by compactor); Ohio DOT, Construction and Material Specifications 2010, Item 304, Table 304.07-1 (4,000 lb per compacted cubic yard, crushed stone); Penn State Center for Dirt and Gravel Road Studies, Driving Surface Aggregate tech bulletin (3/2025); Discount-Equipment.com, Compacting a Base for Pavers (1 in. of lift per 1,000 lb of compaction force). Checked Nov. 13, 2026.
Muthler Landscaping & Construction · Lock Haven, PA
Rather have the base done right the first time?
We build paver patios, walkways and driveways across central PA, base and all.
Get a quotePavers and patios guideAlso: gravel calculator, paver calculator, truck load calculator, patio cost.
Muthler Landscaping & Construction LLC · 913 Bellefonte Ave, Lock Haven, PA 17745 · (570) 397-9800 · PA HIC #PA212584.