A system for parametric modeling of a three-dimensional object has a processor running a software program operable to configure the object by defining a zone comprising a root of a tree hierarchy, the zone having a three-dimensional region defining an outer dimension of the object to be modeled; a part comprising a child of the zone, the part also having a component object to be modeled, wherein the component object is an element of the object; and a variable comprising a child of the part, wherein variable has data defining characteristics of the zone or part. A user interface can display a representation of the three-dimensional object.