Landscaping and Construction Estimating: Cubic Yards for Concrete, Mulch, and Gravel
Never under-order materials again. Learn the cubic yard formula for garden beds, driveways, footings, and patios with practical bagged conversion factors.
The Universal Cubic Yard Formula
In landscaping and masonry, bulk materials (gravel, crushed stone, mulch, and ready-mix concrete) are sold by the cubic yard (27 cubic feet).
Because job measurements are typically taken in feet (length and width) and inches (depth), you must convert inches to fractional feet before multiplying.
Formula: Cubic Yards = (Length in feet × Width in feet × (Depth in inches / 12)) / 27.
Compute required cubic yards and 60lb/80lb bags for slabs, footings, or post holes.
Frequently Asked Questions
How many bags of concrete make one cubic yard?
One cubic yard of concrete requires forty-five (45) 80-pound bags or sixty (60) 60-pound bags.
How deep should landscape mulch be installed?
For new garden beds, a 3-inch depth is recommended for weed suppression and moisture retention. For annual top-ups, 1 to 2 inches is sufficient.