Decomposed Granite Calculator: How Much DG for a Path or Patio?

Updated 2026-10-08 · Yardly

For a garden path, order about 1 cubic yard of decomposed granite per 80–90 sq ft at a 3–4 inch compacted depth (roughly 1.6 tons per yard); a patio base goes deeper at 6 inches, so budget about 1 yard per 55 sq ft. Build it in 2-inch lifts with light water and a plate compactor — never dump the full depth at once, or the bottom never densifies.

DG isn’t gravel — it’s crushed rock dust

Decomposed granite (DG) is pulverized, weathered granite: a mix of fine “fines” and small angular chips that, when damp and compacted, lock into a firm, permeable surface. That’s the opposite of pea gravel or river rock, whose rounded particles never interlock — which is exactly why DG works as a walkable surface and those don’t.

The volume formula is the same one every Yardly calculator uses:

Path: (Length × Width × 3.5 ÷ 12) ÷ 27 = cubic yards compacted × 1.15 for compaction swell × 1.6 = tons Patio: same formula at 6 inches instead of 3.5

Depth goes in inches; the ÷ 12 converts to feet and the ÷ 27 converts cubic feet to cubic yards. The gravel calculator runs this from your exact dimensions and switches between yards and tons.

Depth by use

Surface	Compacted DG depth	Why
Garden path / walkway	3–4 inches	Pedestrian loads only; 4-inch minimum over clay or freeze-thaw soils
Patio (furniture)	6 inches	Concentrated loads from chairs/tables need a deeper, denser pack
Driveway (rare for DG)	8+ inches	Different project; DG isn’t ideal for vehicles

A 2-inch crushed-stone or sand base under the DG gives drainage and a level setting bed — figure that as a separate layer when you price the job.

The 2-inch lift rule

A plate compactor only densifies the top few inches per pass. Spread DG in 2-inch lifts, mist each lightly with a hose (damp like sandcastle sand — clumps but doesn’t drip), and compact before adding the next. Dumping the full depth and tamping once leaves the bottom loose, and a loose bottom consolidates later, taking your surface down with it.

Stabilizer: 5–10% by volume on the top layer

Standard DG is fine for most paths. Add a stabilizer only where you’ll set furniture or see heavy traffic:

• Blend a resin or cement stabilizer at 5–10% by volume into the final lift.
• Compact, then cure 24–48 hours per product directions.
• Reapply a scuffed top layer every couple of years in high-use spots.

The stabilizer doesn’t need to penetrate — a half-inch of bonded surface is enough to cut loose aggregate and rutting.

A worked example: a 40×3 ft path + a 12×12 patio

Path (3.5-inch compacted, 1.15 swell):

• 40 × 3 = 120 sq ft
• 120 × (3.5 ÷ 12) ÷ 27 = 1.30 cubic yards × 1.15 = 1.5 cubic yards → about 2.4 tons

Patio (6-inch compacted, 1.15 swell):

• 12 × 12 = 144 sq ft
• 144 × (6 ÷ 12) ÷ 27 = 2.67 cubic yards × 1.15 = 3.1 cubic yards → about 4.9 tons

Plus a 2-inch crushed-rock base under each: the path base is ~0.9 yard, the patio base ~1.1 yards — run those through the gravel calculator if you’re ordering base and DG together. Finish the DG surface ½–1 inch above adjacent grade so edges don’t wash out, and edge with steel or bender board to contain it.

Keep reading

• Comparing loose-stone surfaces? Pea gravel vs river rock explains why rounded stone won’t pack the way DG does.
• Building the base under a paver patio instead? The gravel calculator and paver patio project estimator total every layer from one set of dimensions.
• Want a full hardscape materials map? The landscape material calculators guide points you to the right Yardly tool for each job.

Frequently asked questions