This paper proposes an algorithm for the automatic generation of Levels-of-Detail (LODs) for 3D polyhedral building models. In this study a group of connected polyhedrons is considered as "one building", after which the generalization is applied to each building consecutively. The most detailed building models used is the polyhedral building model which allows for an elaborate roof structure, vertical walls and a polygonal ground plan. In the work the term "Pseudo-Continuous LODs" is described. The maximum distinguishable "feature resolution" can be estimated from the viewer distance to a building and is used to simplify the building structure by the polyhedron merging and wall collapsing with regularization processes. Experimental results demonstrate that the number of triangles can be reduced as a function of the feature resolution logarithm. Some case studies will be presented to illustrate the capability and feasibility of the proposed method including both regular and irregular shape of buildings.