In the last decades, considerable work has been done regarding service life prediction of buildings and building components. Academics and members of the CIB W080 commission, as well as of ISO TC 59/SC14, have made several efforts in this area and created a general terminology for the concept of service life, which is extremely relevant for property management, life cycle assessment (LCA) and life cycle costs (LCC) analyses. Various definitions can be found in the literature that share common ideas. In fact, there are different criteria that trigger the end of a building’s service life, but the trap that building practitioners too often fall into and that should be avoided is dividing a problem into separate boxes, labels, and specializations without the mutual cohesion and interaction, and ignoring human behavior. Some definitions of service life are discussed in this review paper, in which the cause-effect processes underlying aging and decay are described. These descriptions highlight the continuous interrelation between different criteria for the end of a building’s service life, considering too often neglected and misunderstood causes of the end of life. @en

Housing pathology is the holistic approach to identify, investigate and diagnose housing deficiencies, specify preventive measures and remedial interventions and evaluate their effects. In analogy with health as the core condition for the quality of human life, the health of housing accommodations stands for housing quality, being the ability of residential buildings to fulfil adequate shelter for specified groups of residents. The relevance of housing and building pathology as a relative new knowledge field lies in the paradigm shift from new construction to maintenance and adaptation of the existing housing stock that occurs in most western countries, but also in the fast growing urban areas in developing countries. To maintain the fast ageing housing stock in developed countries as well as to shelter the growing population in emerging economies in a durable and sustainable way, the service life span has to be optimally extended. The impending assignment to reduce the ecological footprint and CO2 and N2 emissions of the construction and housing sector – also a major paradigm shift - requires major adaptations of homes and services as well as of the mindset and behaviour of builders, managers and residents. For the implementation of the Paris Climate Action Agreement, knowledge based sustainable stock management and adaptation will be indispensable. Though it is the combination and interference of technical, social, spatial and economical processes that is determining for the health and life span of housing stocks, they are hardly interdisciplinary studied nor integrated in practical knowledge, let alone in a pathological context. The existent theoretical and applied knowledge about the different fields of housing stock management – in particular life span, life cycle and quality condition management is up to now too limited and segmented to successfully fulfil the new assignments. Rearrangement in a comprehensive pathological domain appears as an obvious solution. This paper defines and explores the knowledge the knowledge required for the coming assignment, overlooks the available knowledge and shortcomings, the field of application, the main diagnostic tools and instruments and the practice in housing management. The paper concludes with the necessity of better holistic, building type and behaviour directed pathological knowledge and further international interdisciplinary research cooperation.@en

What is the average lifespan of dwellings? Though of decisive importance for the provision, maintenance and management of housing stocks, and despite a choice of research papers about the subject, the last word about this question is far from said. At first a distinction should be made between the technical lifespan and the functional service life. The technical lifespan is decisive for the physical existence of a dwelling, the service life for the length of time that a dwelling fulfils the functional needs of households. This distinction is not always clear in the available research sources which show a wide range of approaches, varying from ex-ante assessment of the physical condition and estimation of the residual technical lifespan, financial analyses of the profitable service life and/or depreciation period through ex-post mortality analyses in analogy to human mortality. Most ex-ante approaches start from a limited scope; an all-encompassing interdisciplinary approach is missing. On the other hand ex-post analyses suffer from the fact that – in contrary of human populations – buildings are man-made, -managed and -demolished; the vast majority of housing stocks is very young and consistent longitudinal series are missing. As a result, none of these approaches leads up to now to useful results, let alone reliable predictions. As the technical lifespan of a dwelling as a whole strongly depends on its numerous different components, knowledge of technical lifespans of dwellings and building component is also of decisive importance for ex-ante environmental life cycle assessments and life cycle cost calculations. Based on an overview of the available sources, the paper discusses the pros and cons of the existing knowledge, possible improvements and alternatives.@en

Obsolescence, defined as the process of declining performance of buildings, is a serious threat for the value, the usefulness and the life span of built properties. Thomsen and van der Flier (2011) developed a model in which obsolescence is categorised on the basis of two distinctions, i.e. between endogenous and exogenous cause-effect relationships and between physical and behavioural cause-effect relationships. In this way, the model presents a classification of underlying factors of obsolescence. However, these underlying factors, more specifically the underlying cause-effect relations, are still a black box. In this paper, the box is further disclosed by tracking back the underlying processes, resulting in a series of prototypes of detailed hypothetic cause-effect mechanisms. Applied to the adapted model, the results are initially tested on an iconic chocolate factory. Conclusions are drawn about the results and more generally about the usability and the further development of the model.@en

Minister Blok stuurde medio april zijn omstreden wetsvoorstel Kwaliteitsborging voor de bouw naar de Tweede Kamer. De consumentenorganisaties verenigd in de Woonalliantie wijzen het wetsontwerp als geheel af.@en