This paper presents an efficient method for reconstructing 3D building models from Electronic Architectural Drawings (EADs). EADs are matched via recognising axes and elevation. After recognising Candidate Contours (CCs) of Architectural Components (ACs) in one floor plan, the method incorporates the results into recognising the neighbour floors, which is achieved by a mapping algorithm. CC classification is proposed to reduce the interaction for 3D reconstruction. A parameterised 3D model database is used to improve details of reconstructed results. Our method requires some interaction as guidance. The experimental results show that ordinary users could create a 3D building model that consists of over 100 components in several minutes.