Soils reports, also called “geotechnical soils reports” are prepared by a licensed geotechnical engineer or a registered civil engineer experienced in soils engineering. A soils report may be required depending on the building site. The report gives understanding of earth conditions affecting a building. They are required in areas with expansive or low strength soils. Other times a soils report may be required include buildings where the foundation will be supported by fill, projects on steep slopes or where a lot of grading will be done, locations with high ground water or those within FEMA floodplains. Soils reports are obtained before construction begins.
The engineer who designs the foundation uses the soils report in determining what kind of foundation design to use. In this way, problems such as differential settling over time can be avoided. There are various methods used to test soil in preparing a report. These include drilling core samples, driving steel rods into the soil to determine density and the presence of rock, test pits and the use of a seismograph.