Geotechnical Issues Geotechnical reports, also called “soils reports” are prepared by geotechnical engineers or civil engineers experienced in soils engineering. They are recommended when the house is near a steep slope or a bluff, or when the soil is unusually soft.  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.

A geotech report can tell you if a bluff is a landslide waiting to happen or if a slide would be unlikely.  Sometimes, the concern is not about a catastrophic slide, but that the slope could be slowly "creeping" away.  

The report can also recommend improvements such as a drainage system or grading alterations, or where to locate structures to minimize risk.   

This report should be obtained before construction begins, however, especially if you are buying an older house, it may not have been done. If there are concerns, first ask the seller if they have a report for you to review.  If not, consider getting your own.  

If a report is available, read it carefully and verify that all recommendations were followed.  I have seen cases where the recommendations of the engineer were ignored by the builder.      

The foundation in the photo below is failing: the crack is over one inch wide.  The problem is not with the foundation, it is that the house is on a steep hillside, and the hill is slowly sliding away.