Foundation (engineering)
Foundations are designed to have an adequate load capacity depending on the type of subsoil/rock supporting the foundation by a geotechnical engineer, and the footing itself may be designed structurally by a structural engineer. The primary design concerns are settlement and bearing capacity. When considering settlement, total settlement and differential settlement is normally considered. Differential settlement is when one part of a foundation settles more than another part. This can cause problems to the structure which the foundation is supporting. Expansive clay soils can also cause problems.
Flounder house
The motivation for building flounder houses is debated. Common folklore follow one of three themes: "a result of an early restrictive building ordinance, the original owner's plan for future expansion, or a desire to reduce property taxes."
In fact, shed roofed buildings are often simply the cheapest to construct.