As every builder knows numbers of buildings are damaged each year because of inadequate foundational support. However, a builder only would have to pay about one-fifth of one per cent of his building cost to assure that the ground he builds on is adequate. And although it could be argued that everything about a structure is the owner's responsibility, in footing the bill he is delegating the responsibility to the man most likely to be the most knowledgeable about the subject: the building contractor. The first thing you want to do is check the reports published by the US Geological Survey. After this, buy a soil auger. It should be small enough to be operable by hand, yet large enough to yield a good sample. You are looking for soil that won't slide, won't compress under weight, won't swell when wet, and won't shrink and crack when dry. There are several different types of soils. The first is bedrock. This is not a soil, but when you have it soils don't matter as long as the bedrock is free of faults and cavities. Sampling should be carried out over a large enough area so boulders are not mistaken for bedrock. The second type is boulders, gravel, and sand. These are described as coarse-grained or strong soils because they resist deformation by means of friction, whereas the fine grained soils depend of cohesion of the particles. For all practical purposes, these are equal to bedrock if properly compacted. Suspect soils are silt, clay, organic material, and fill if they can be stressed by the building load.