Stone foundations are usually seen in older homes. They were seldom used in construction dating after WW II. Stone foundations can be prone to settling and water seepage. A unique problem to stone foundations is that the foundation itself can be a source of Radon gas, which is an environmental hazard. This type of installation is also prone to such problems as settling and water seepage. A stone foundation when maintained well is a very aesthetically appealing installation, but must be inspected carefully. Joints wear quickly because they are usually not smooth and uniform. Shifting or settling can occur because of the uneven nature of stones.