Please Enter Width In Foot. As you probably know foundation walls and stem walls need different calculations. That means a 80-pound bag of concrete mix will yield 06 cubic feet of concrete a 60-pound bag will yield 045 cubic feet and a 40-pound bag yields 03 cubic feet.
Pre-mix concrete comes in bags that are 60 lbs.
If you have concrete delivered it is sold by the yard which is a cubic yard. The formula for cubic yards is this. Using measurements in feet. That means a 80-pound bag of concrete mix will yield 06 cubic feet of concrete a 60-pound bag will yield 045 cubic feet and a 40-pound bag yields 03 cubic feet.