Concrete Wall Calculator
Enter a wall's length, height, and thickness to get cubic yards to order, bag counts, and a bags-vs-truck call — waste built in.
bags = ceil(106.7 × 1.1 ÷ 0.6) = 196
A poured concrete wall or footing is just a long box standing on edge, so its volume is length × height × thickness. The calculator works in that order: it multiplies the three dimensions for the raw volume, adds a waste allowance for over-excavation and form deflection, then converts the padded volume into the cubic yards you would order from a ready-mix plant and the number of 60 or 80 lb bags it would take to mix by hand.
Thickness is usually given in inches while length and height are in feet, so the tool divides thickness by twelve before multiplying — that keeps everything in cubic feet, which it then turns into cubic yards (÷ 27) and into bag counts using each bag's published yield: an 80 lb bag of standard mix makes about 0.60 cubic feet and a 60 lb bag about 0.45. Bag counts always round up, because a partial bag is not something you can buy.
Walls add up fast. A short garden wall might be a few bags, but anything with real length crosses into ready-mix territory quickly, so the calculator flags when your order passes about 1.5 cubic yards — the point where a truck usually beats bags on both cost and the quality of a single continuous pour.
volume = 20 × 8 × (8 ÷ 12) = 106.67 cu ft → +10% = 117.33 cu ft
order = 117.33 cu ft ÷ 27 = 4.3 cu yd (3.32 m³)
80 lb bags = ceil(117.33 ÷ 0.60) = 196 · 60 lb bags = ceil(117.33 ÷ 0.45) = 261