Labor, other materials, taxes, etc, NOT included!
|Monolithic Slab? No problem. Compute center area first then compute "footer" area next and add the two results together.
Pole Barns? Do the same thing except that your "footer" will be the area under each pole.
Note about price: When using bags, the price will usually be much higher than calling a truck unless the project is very small. Call your local supplier for the price per bag.