International Journal of E-Planning Research, 1(4), 35-58, October-December 2012 35 Copyright © 2012, IGI Global. Copying or distributing in print or electronic forms without written permission of IGI Global is prohibited. Keywords: 3D Cadastre, Building Information Model, City Geography Markup Language (CityGML), Industry Foundation Classes (IFC), Unifed Building Model (UBM) INTRODUCTION This section provides a general background to the cadastre use and development followed by a discussion over the purpose and objectives of this study. Background to Cadastre A cadastre is a register of real estates in a country. It may be defined as a parcel based and up-to-date land information system that includes important records on land such as rights, owner- Feasibility of Building Information Models for 3D Cadastre in Unifed City Models Mohamed El-Mekawy, Department of Computer and Systems Sciences, DSV, Stockholm University, Stockholm, Sweden Anders Östman, Faculty of Engineering and Sustainable Development, University of Gävle, Gävle, Sweden ABSTRACT The current cadastral systems are usually based on a 2D parcel maps and land registries having references to different documents. In many countries, the parcel maps, as well as the registries and referenced documents, are represented digitally. The 3D cadastral systems have usually a similar approach, where the descriptions of the 3D components are represented by drawings in PDF format. This article focuses on creating the 3D geometries corresponding to 3D property based on existing 3D building models. The article investigates shortages of IFC and CityGML, the most prominent semantic building models for representation of BIM and geospatial models respectively, as well as a unifed building model (UBM) that was developed earlier for modelling complete and real 3D cadastre information system. The result shows that IFC, CityGML, nor the UBM has capabilities for such tasks. The article proposes an extension to the UBM in adding different subtypes to the boundary surfaces above and underground. The extended UBM is then implemented in a case study of a hospital building in Sweden. The implementation shows that by adding the four subtypes “Building Elements Surfaces,” “Digging Surfaces,” “Protecting Area Surfaces,” and “Real Estate Boundary Surfaces” of boundary surfaces, it has become possible to model all the needed surfaces that defne 3D cadastral in- formation of a building. DOI: 10.4018/ijepr.2012100103