AsphaltTons.com — asphalt tonnage calculator

How Much Concrete for a 15x60 Slab?

For a 15x60 slab poured 4 inches thick, plan on about 11.11 cubic yards of concrete. That comes from 900 square feet times 0.333 feet of depth, divided by 27. How much concrete for a 15x60 slab at other thicknesses is in the table below.

Concrete calculator →

The math for a 15x60 slab

  1. Area: 15 ft × 60 ft = 900 sq ft.
  2. Thickness in feet: 4 in ÷ 12 = 0.333 ft.
  3. Volume: 900 × 0.333 = 300.0 cubic feet.
  4. Cubic yards: 300.0 ÷ 27 = 11.11 yd³.
  5. With 10% extra: 12.22 yd³.

The concrete calculator runs the same steps for any size and thickness.

Concrete for a 15x60 slab by thickness

ThicknessCubic feetCubic yardsYards +10%80 lb bags60 lb bags
4 in300.011.1112.22500667
5 in375.013.8915.28625834
6 in450.016.6718.337501,000

Bag counts assume about 0.60 cubic feet per 80 lb bag and 0.45 per 60 lb bag, rounded up.

Thickness for this job

Four inches is the usual thickness for patios, walks and shed floors. Slabs that carry cars or a heavy hot tub are often poured at 5 to 6 inches, and edges are sometimes thickened where loads concentrate.

Ordering ready-mix

A cubic yard of concrete is 27 cubic feet and weighs roughly 4,000 pounds. Most ready-mix trucks carry up to about 9 to 10 yards, though local trucks and rules vary. If your total is under a yard or two, bagged mix or a short-load supplier may be cheaper.

Base and forms

Prep matters as much as the yardage. Strip sod and soft soil, compact the subgrade, then add a compacted stone base, commonly about 4 inches. A level, firm base also keeps your thickness even, which keeps the yardage close to the math.

Keeping cracks under control

Reinforcement does not stop cracks, but it holds them tight. Wire mesh or rebar set mid-depth on chairs is common for a slab that carries vehicles; fiber-reinforced mix is an option for light-duty slabs. Joints about 8 feet apart control where cracks form.

Questions people ask

How many yards of concrete for a 15x60 slab at 4 inches?

About 11.11 cubic yards, or 12.22 with 10 percent extra.

How many yards for a 15x60 slab at 6 inches?

About 16.67 cubic yards.

How many 80 lb bags for a 15x60 slab?

About 500 bags at 4 inches thick, before any waste allowance.

How many square feet is a 15x60 slab?

900 square feet.

How many 80 lb bags make a cubic yard?

About 45. Each 80 lb bag yields roughly 0.6 cubic feet, and a cubic yard is 27 cubic feet.

When is bagged concrete practical?

Usually for jobs under about a cubic yard. Beyond that, mixing dozens of bags by hand gets slow and batches may not blend well.

Related guides

Open the concrete calculator → Asphalt tonnage calculator →

As an Amazon Associate, AsphaltTons.com earns from qualifying purchases. Product links below are sponsored.

Related answers