To produce one cubic yard of concrete, you generally need about 45 bags of 80-pound concrete mix or about 90 bags of 40-pound mix
. This is a standard estimate used in the industry and is based on the volume yield of each bag size.
- One cubic yard equals 27 cubic feet.
- Each 80-pound bag yields approximately 0.022 cubic yards of concrete.
- Therefore, 1 cubic yard ÷ 0.022 cubic yards per bag ≈ 45 bags of 80-pound concrete
If you are pouring a slab that is 4 inches thick over an area of one square yard, you would need about 20 bags of 80-pound concrete because the volume is less (about 0.333 cubic yards)
. In summary:
- For a full cubic yard of concrete: about 45 bags of 80 lb.
- For smaller volumes, calculate the cubic yards needed and multiply by the number of bags per yard accordingly.
Because mixing so many bags is labor-intensive, ready-mix concrete delivery is often more practical for large projects
