Termites start in soil
Subterranean termite colonies usually
start below ground on wood debris left
behind during construction. Once inside a
structure termites extend
the colony by building "shelter tubes"
over, or inside, the foundation that spans between
the soil and building (see drawing below). In
short -- anything that links the soil to the
building can serve for termite access.
Termites enter houses through a number of
"weak points" (right) such as foundation walls and
posts. These areas should be regularly inspected for termite
Shelter tubes also provide a means to
control termites, see Termite