The foundation is the substructure of a building that provides a solid base upon which the superstructure can rest. The type of foundation, and its specific design, are dictated by the total load of the building, the type, and quality of soils in which it will rest.
For all intents and purposes, there are two main categories of foundations, Shallow foundations and Deep foundations:
Shallow Foundations- any foundation system that is directly below the lowest part of a substructure, where the pressures are transfered to the ground directly via vertical pressure. They can consist of:
Deep Foundations- any foundation system that extends down through unsuitable soils to transfer building loads to suitable bearing strata, typically bedrock. They can consist of: