This paper presents results of a research towards risks in design and building processes with respect to structural safety in contemporary building projects. 15 almost or just finished building projects with different functionalities and different clients were subject of the research. Different ways of cooperation (traditional, design & construct, building team, turn key) were represented. After document reviews, interviews and site visit with visual inspection, for each project a report with the main facts of the organization of the process, the structural design, costs and fees and interventions related to structural safety was written and verified by the client's project manager. A risk table was developed in which for each stage of the project risks are distinguished that could lead to the top risk: lack of structural safety. The individual building projects were evaluated. In 12 of the 15 projects interventions related to structural safety occurred. These led to modifications or strengthening of already executed structures. Assessment of the risks and the way these risks were controlled result in an appraisal of the proof of structural safety and the level of risk control. It is concluded that parties in an individual building project do not always have the same view of structural safety, that in most projects no specific decisions are made about the level of structural safety and that the type of contract seems to have no relation with the level of risk control.

<p>The paper presents the results of an investigation on collapsed roofs in the Netherlands after heavy snowfall in November 2005. Based on meteorological data and local observations and measurements the actual snow load which occurred is estimated and compared with statistical information. A comparison between the actual maximum snow loads and the snow load dictated in the code shows that both are of the same magnitude. The results of the investigations to the causes of collapse of 21 roofs are considered. In 14 cases design mistakes are assigned as (one of) the causes; also execution mistakes and lack of durability are assigned in several cases. In only 2 cases exceeding of the design load is assigned as (one of) the causes.<p> The findings of another research in the Dutch project “Learning from failures” are referred to. In that project the causes of the collapse of structures are related to organizational aspects in design and execution, as source of failures or condition in which structural failures can be expected.<p> It is concluded that the snow loads as they are described in the code seem to be in accordance with the chosen frequency of occurrence but that the resistance of structures in many cases is less than could be expected based on the requirements of the code. A program to get more insight in the status quo of structural safety in recently designed and realized buildings is initiated.