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How to build a concrete foundation
Choose the type of foundation to build.
The type of foundation depends on the area of the foundation will be located on and the type of structure that will be placed on it.
Shallow foundations are built on level ground and hard surfaces.
Shallow foundations are no more than 3 feet (91.44 cm) deep and are used primarily for smaller, simpler projects like holding patio furniture, a fountain, or an air conditioning unit. Deep foundations are used for more complex projects.