Construction zones are geometric units of work in the construction planning process. Using construction parameters and geometric properties, construction zone generation mechanisms change the level of detail of the 3D geometry and corresponding activities of the planned project. We have defined and implemented a set of mechanisms for construction zone generation. Decomposition provides various ways to generate detailed zones, while aggregation generates combined zones. To support these mechanisms, we have formalized a geometric representation based on triangular meshes that can represent the activity workflow, project spatial hierarchy, local variations in productivity, and activity state information on a component at any given time. This paper summarizes the mechanisms and describes various planning/scheduling applications of these mechanisms, such as rapid plan evaluation, resource and workflow balancing in 3D, and association of schedules at multiple levels of detail. Our contributions are the formalization of these zoning mechanisms, representation and algorithms to support these mechanisms, and planning/balancing methods utilizing the mechanisms.