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Bags of River Rock for a 4x25 Walkway

How many bags of river rock for a 4x25 walkway: at 3 inches deep you need about 25.0 cubic feet, which is 50 bags of the common 0.5 cubic foot size. If your store sells river rock in 50-pound bags instead, figure about 50 bags, since river rock 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 in8.31717
2 in16.73434
3 in25.05050
4 in33.36767

How to figure it

  1. Area: 4 × 25 = 100 sq ft.
  2. Volume: 100 × (3 ÷ 12) = 25.0 cu ft.
  3. Bags: 25.0 ÷ 0.5 = 50 bags (round up).

Bags or bulk?

A cubic yard is 27 cubic feet, so 25.0 cubic feet is 0.93 yards, about 1.2 tons. Under a yard, bags save a delivery fee and are easy to haul in a car or pickup. Compare the bag price × 50 against a bulk quote for 1.4 tons delivered.

About river rock

River rock is smooth, water-worn stone sold in sizes from about 3/4 inch to several inches. Larger sizes cover fewer square feet per ton at the same depth because the voids between stones are bigger.

Before you spread 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 rake smooth; rounded stone will not 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.

When to choose river rock

Good uses:

  • Dry creek beds and drainage swales
  • Decorative borders and planting beds
  • Around downspouts to stop splash erosion

Think twice for:

  • Walking surfaces
  • Driveways
  • Bases under slabs or pavers

Quick reference numbers

  • Per inch over 100 sq ft: about 0.42 tons of river rock (0.31 cubic yards).
  • Per inch over 1,000 sq ft: about 4.2 tons.
  • Another size for comparison: a 20x25 area at 3 inches takes about 6.3 tons.
  • Weight used here: about 1.35 tons per cubic yard.

Mistakes that throw off the order

  • Using inches as if they were feet. Depth has to be divided by 12 before you multiply; skipping that step inflates the order twelvefold.
  • 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.
  • Forgetting that compaction shrinks loose material. A loose 4-inch spread of a dense-graded stone may finish closer to 3 inches after rolling.

Questions people ask

How many bags of river rock for a 4x25 walkway?

About 50 bags of 0.5 cubic feet at 3 inches deep.

How many 50 lb bags of river rock for 4x25?

About 50 bags at 3 inches.

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

54 bags.

How many cubic feet is a 4x25 walkway at 3 inches?

About 25.0 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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