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Bags of Decomposed Granite for a 4x100 Walkway

How many bags of decomposed granite for a 4x100 walkway: at 3 inches deep you need about 100.0 cubic feet, which is 200 bags of the common 0.5 cubic foot size. If your store sells decomposed granite in 50-pound bags instead, figure about 200 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 in33.36767
2 in66.7134134
3 in100.0200200
4 in133.3267267

How to figure it

  1. Area: 4 × 100 = 400 sq ft.
  2. Volume: 400 × (3 ÷ 12) = 100.0 cu ft.
  3. Bags: 100.0 ÷ 0.5 = 200 bags (round up).

Bags or bulk?

A cubic yard is 27 cubic feet, so 100.0 cubic feet is 3.70 yards, about 5.0 tons. Past about a yard, bulk is usually less work and often less money. Compare the bag price × 200 against a bulk quote for 5.5 tons delivered.

About decomposed granite

DG should be laid in thin lifts, wetted and compacted. Loose DG at a deep depth stays soft and tracks onto shoes.

Install tips for a walkway

  • 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

Think twice 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 20x25 area at 2 inches takes about 4.2 tons.
  • Weight used here: about 1.35 tons per cubic yard.

Mistakes that throw off the order

  • Ignoring the base. A thin surface layer over soft soil fails early no matter how much material is on top.
  • Measuring only the main rectangle. Aprons, turnouts and curved edges add real square footage.
  • Using inches as if they were feet. Depth has to be divided by 12 before you multiply; skipping that step inflates the order twelvefold.
  • Skipping drainage. Water sitting under any surface softens the base and leads to ruts and potholes.

Questions people ask

How many bags of decomposed granite for a 4x100 walkway?

About 200 bags of 0.5 cubic feet at 3 inches deep.

How many 50 lb bags of decomposed granite for 4x100?

About 200 bags at 3 inches.

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

54 bags.

How many cubic feet is a 4x100 walkway at 3 inches?

About 100.0 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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