Condominium is one of the prevalent forms of three- dimensional (3D) property rights (Paulsson, 2007, p. 32). The condominium concept common to a number of jurisdictions consists of three elements: (a) individual ownership of an apartment, (b) co-ownership (joint ownership) of the land and the common parts of the building, and (c) membership of an incorporated or unincorporated owners' association (van der Merwe, 2015, p. 5). The ownership shares of condominium unit owners in the common property are here referred to as co-ownership shares; yet, alternative terms include ownership fraction, condominium share, participation quota, share value, and unit entitlement. The co-ownership share determines the proportional contribution to the common expenses and the share of common profits, as well as the voting power of each condominium unit owner in the administration of the condominium. The most common approaches to the determination of the co-ownership shares are based on equality, relative size or relative value of each condominium unit, or a combination of such (van der Merwe, 1994, p. 57-58). The literature presents detailed descriptions and comparative analysis related to condominium systems in different jurisdictions (e.g. van der Merwe, 2016; 2015; Paulsson, 2007; EUI, 2005; UNECE, 2005); however, the technical and procedural aspects related to the allotment of co-ownership shares still need to be further investigated. This paper aims to compare methods and procedures applied for the allotment of co-ownership shares of condominium systems in the following seven jurisdictions; Denmark, Germany, South Africa, Sweden, Switzerland, the Netherlands, and Turkey. Also, international geographic information standards (i.e. ISO LADM, OGC LandInfra/InfraGML) are analyzed to assess the extent to which they facilitate allocation of co-ownership shares. The main purpose is to clarify the legal provisions and methodologies related to the determination of co-ownership shares in national condominium systems and bring new insights to countries, which are trying to revise their national provisions for fairer implementations.@en

In the construction industry, business relationships are often short-term and one-off. There are many unique processes and activities. The resulting complexity and fragmentation may obstruct quick and effective exchange and integration of information and thus hamper project progress. Building Information Modelling (BIM) aims at preventing mismatches in information exchange between the many stakeholders. Although BIM has come a long way in this respect, there are still challenges to overcome. The authors explain the essentials of BIM and discuss issues. @en

Spatial data in a Land Administration (LA) establish a fundamental geospatial data theme (see UN GGIM, 2018) and the integrated geospatial information framework for any Spatial Data Infrastructure (SDI). Domain-specific standards, an integral component of the SDI, play an essential role to represent the semantics of domains, specify links between distributed registries and databases, and stimulate the development and implementation for Land Administration Systems (LAS). As an international descriptive standard providing an abstract conceptual schema, the ISO 19152:2012 Land Administration Domain Model (LADM) has been used and is being used as a reference for the implementation of LAS. Various approaches have been used for the LADM implementation that includes elaborating (via a country profile) and realizing a technical model suitable for the implementation (van Oosterom and Lemmen, 2015). LADM focuses on a specific function of LA that is interested in Rights, Responsibilities and Restrictions (RRR) affecting land, and the geometrical components thereof. The land value function of LA is considered outside the scope in the first edition. Recently, for extending the flexible and modular basis of the LADM, a valuation information model is developed for the specification of valuation information maintained by public authorities. It identifies the links between property valuation and the other LA registries and databases (e.g., cadastre, land registry, building and dwelling registries) that may enable interoperability across systems. The conceptual schema of the model provides a common basis to direct the development of local and national valuation databases and information technology products and services, following an approach similar to the LADM implementation. The proposed LADM Valuation Information Model is on the agenda of the development of the second edition of LADM within ISO/TC211. The operability of the newly proposed conceptual model needs to be evaluated through technical implementation. This paper describes the development of a prototype for the implementation of the LADM Valuation Information Model and assesses its operability through a case study for Turkey. The primary aim of the paper is to test the capabilities of the LADM Valuation Information Model using the required and produced data in recurrent valuation processes, but not to build a specific information management system for Turkey. As the implementation of a LADM compliant prototype initially requires the development of a country profile at conceptual level, methodologies applied for LADM profile development are examined and then a Turkish LADM Valuation Information Model country profile is proposed using the Conceptual Schema Languages (CSL) of the Unified Modelling Language (UML) and INTERLIS. INTERLIS is a formal language as well as a set of software tools that support LADM implementations. Subsequently, approaches and tools used in the LADM implementation are investigated and utilized for the automated transformations from the country profile to several technical models. In this context, the article presents the experiences gained during the implementations. Moreover, strategies for implementing and managing property valuation information more efficiently (e.g. bi-temporal aspects of valuation information management) are also studied and applied to the implementation. The generated technical models are then populated with sample datasets related to recurrent property valuation including the geometries of valuation units, as well as valuation information covering several years. The developed prototype is then tested through a number of queries to assess whether the LADM Valuation Information Model fulfils information management needs of recurrent valuations. The main contribution of this paper is to provide a holistic approach on how to develop an LADM conformant prototype for managing property valuation information.@en

Property valuation is a process of estimating value of an immovable property. The legal, geometric, physical and environmental characteristics of the immovable property together with the economic indicators are taken into consideration during this process. Traditional cadastral systems only provide two-dimensional (2D) legal and geometric information about property units. However, today’s complex valuation practices (e.g. computer aided mass appraisal) would benefit significantly from three dimensional (3D) information on not only property units but also their physical counterparts (e.g. buildings, building parts). Moreover, 2D and 3D environmental information is needed for determining environmental conditions about immovable properties to better estimate the values of them. A collaborative research initiative has proposed an international valuation information model that extends the LADM for specifying semantics of valuation registries maintained by public authorities. The current version of the LADM Valuation Information Model, however, does not include detailed specification for the environmental characteristics of immovable properties (e.g. presence of views, level of visibility and distance to amenities) which can be derived with 2D and 3D geospatial analyses by means of various data sources. The purpose of this paper is to examine which geospatial analyses, especially 3D analyses, can be used to provide information about immovable properties including environmental and locational characteristics for property valuation activities. Furthermore, it is investigated that how property valuation can benefit from data sources including semantically rich 3D building, city and cadastral models for deriving environmental and locational characteristics of property units. To achieve these objectives, the data sources and geospatial analyses are initially investigated in the context of property valuation. Then, the paper focuses more on viewshed analysis. By using open topography, building and height datasets of the Netherlands and 3D GIS analysis, a viewshed analysis is presented to show how it can be utilized using different data sources for better understanding and explanation of values of the properties. The paper is concluded with a discussion to what extent it is possible and meaningful to include (derived) environmental characteristics of properties in the LADM Valuation Information Model.@en