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Bags of Decomposed Granite for a 14x18 Patio

How many bags of decomposed granite for a 14x18 patio: at 3 inches deep you need about 63.0 cubic feet, which is 126 bags of the common 0.5 cubic foot size. If your store sells decomposed granite in 50-pound bags instead, figure about 126 bags, since decomposed granite weighs roughly 100 pounds per cubic foot.

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Bag count by depth

DepthCubic feet0.5 cu ft bags50 lb bags (approx.)
1 in21.04242
2 in42.08484
3 in63.0126126
4 in84.0168168

How to figure it

  1. Area: 14 × 18 = 252 sq ft.
  2. Volume: 252 × (3 ÷ 12) = 63.0 cu ft.
  3. Bags: 63.0 ÷ 0.5 = 126 bags (round up).

Bags or bulk?

A cubic yard is 27 cubic feet, so 63.0 cubic feet is 2.33 yards, about 3.2 tons. Past about a yard, bulk is usually less work and often less money. Compare the bag price × 126 against a bulk quote for 3.5 tons delivered.

About decomposed granite

Decomposed granite (DG) is weathered granite broken into small particles and fines. It packs into a firm, natural-looking path surface, and stabilized versions include a binder.

Install tips for a patio

  • Dig and level. Remove sod and set the base slightly below the surrounding grade.
  • Edge it. Steel, plastic or stone edging keeps material in place.
  • Spread in layers. Rake to depth, then tamp or wet and compact.
  • Buy a few extra. Grab 5 to 10 percent more bags for settling and touch-ups.

The volume and tonnage calculator handles other sizes and depths.

Good and poor uses for decomposed granite

Works well for:

  • Garden paths and patios with a natural look
  • Around trees and in xeriscape designs
  • Stabilized DG for accessible paths

Poor fit for:

  • Steep grades without a stabilizer
  • Areas right outside doors, since fines track in
  • Driveways with heavy turning traffic

Quick reference numbers

  • Per inch over 100 sq ft: about 0.42 tons of decomposed granite (0.31 cubic yards).
  • Per inch over 1,000 sq ft: about 4.2 tons.
  • Another size for comparison: a 15x30 area at 4 inches takes about 7.5 tons.
  • Weight used here: about 1.35 tons per cubic yard.

Common estimating mistakes

  • Assuming every supplier uses the same weight. Two yards selling the same product name can quote different tons per yard.
  • Mixing up cubic yards and tons. Yards are volume, tons are weight; convert with the product’s weight per yard.
  • Ordering exactly the math. Uneven ground and spillage nearly always need a little more than the flat calculation.
  • Measuring only the main rectangle. Aprons, turnouts and curved edges add real square footage.

Questions people ask

How many bags of decomposed granite for a 14x18 patio?

About 126 bags of 0.5 cubic feet at 3 inches deep.

How many 50 lb bags of decomposed granite for 14x18?

About 126 bags at 3 inches.

How many 0.5 cubic foot bags are in a cubic yard?

54 bags.

How many cubic feet is a 14x18 patio at 3 inches?

About 63.0 cubic feet.

When does bulk make more sense?

Usually once the job passes about a cubic yard, or when you would need more than a few car trips.

Related guides

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