As mentioned before, the stability of the soil as a foundation material is a critical and key point which can essentially direct the design of the building. The different factors that come into play when determining the suitability of the soil on site are stratification, composition, density of the soil bed, variations in particle size, presence or absence of ground water.

Another important element to consider within soil types on site is the water table. The presence of ground water can be harmful and can reduce the bearing capacity of the soil, thus, any groundwater should be removed. This also relates to the soil types present where the coarse grained soils drain better and are more permeable whereas the fine grained soils such as silt and clay are less permeable.