Decomposed Granite Calculator
Calculate the tons of decomposed granite for paths and patios.
What you'll need to order
- decomposed granite
- stabiliser binder
- geotextile fabric
- metal edging
Prices vary by region and haul distance. Get quotes from at least two local suppliers.
How this calculator works
tons = length × width × (depth ÷ 12) × 110 ÷ 2000
Decomposed granite weighs about 110 lb per cubic foot once compacted, and loses roughly a quarter of its loose volume when rolled. The headline figure is compacted depth; the order figure adds that 25% back.
Worked example
With length 10 ft, width 10 ft, compacted depth 3 in, this calculator returns 1.38 tons.
Waste allowance
The headline figure includes a 25% allowance for waste and over-ordering. The exact requirement is shown alongside it.
Frequently asked questions
How much decomposed granite do I need?
Multiply area by depth in feet, then by 110 and divide by 2,000 for compacted tons. A 40 by 4 ft path at 3 inches deep needs 2.2 tons compacted, so order about 2.75 tons loose.
Does decomposed granite need a binder?
For a firm, low-maintenance surface, yes. Stabilised DG mixed with a binder resists erosion and tracking. Plain DG is cheaper but washes out on slopes and gets carried indoors on shoes.
How deep should decomposed granite be?
Two to three inches compacted for a pathway, and four inches over a compacted base for patios or vehicle traffic. Deeper than that stays soft and rutted underfoot.
Is decomposed granite good for a driveway?
Only with a stabiliser and a proper compacted base beneath it. Unstabilised DG rutted by tyres needs regular regrading, whereas a stabilised installation over road base holds up for years.