Foundation footing construction begins even prior to site location. The engineering for the construction site must take into account various soil conditions. Site engineering for a structure always includes engineering considerations for about bearing points of a structure.
After site selection, soils experts are called in to determine the depth and which the foundation must be placed in order in to accommodate all live and dead loads. Dead loads are easily assessed but the live loads are much more difficult to determine. Another consideration during this course of construction would be the relationship between the height of the st