The definition of a basement is when part of the building is wholly underground. This space is generally used as additional living space. There are regions of the United States where basements are very common. However, in the Pacific Northwest, you will find they are not as common. Part of the reason is due to the high water table. Some home sites are sloped, which may require a stepped foundation. If your home site requires a stepped foundation it will require additional engineering and materials which increase the cost to build. For more information please connect with a Home Consultant in your region to discuss your specific needs.