A simplified replacement cost model for residential buildings located in developing countries: The case study of Colombia

To reduce disaster impacts, initiatives have been promoted to assess seismic risk in developing countries like Colombia. To achieve this, it is crucial to develop exposure models that consolidate parameters of assets that may be affected by a seismic event, including their geographic location, material, structural system, and economic value. This last parameter is often assessed by using the asset replacement cost. Replacement cost valuations are often based on rough estimates that overlook factors like demolition, material transport, land suitability, structural typology, and regional socioeconomic dynamics. This study focuses on developing a simplified national replacement cost model for residential buildings in Colombia, a country that exemplifies the complexities and unique characteristics among developing nations. Colombia’s diverse seismicity, topography, socioeconomic disparities, and varied climatic conditions present an ideal case for examining how a streamlined approach for cost estimation can be implemented and effectively used. Within the framework of the open National Seismic Risk Model (MNRS), the proposed methodology includes over 50 representative combinations of materials and structural systems obtained from the available exposure models of the country. The model integrates traditional construction costs of common building types with variables reflecting current socioeconomic conditions and regional transportation dynamics. The research highlights the importance of including indirect costs and transportation dynamics for accurate nationwide replacement costs. The regional models, calibrated to reflect local socioeconomic and logistical dynamics, demonstrate a range of fit that varies significantly across regions. This variability highlights the importance of calculating replacement costs using a regional approach rather than assuming a homogeneous national model. The study also shows that reinforced concrete systems, especially moment-resisting frames, are costlier than masonry-based systems. The model updates Colombia’s exposure models in the MNRS, providing a crucial tool for decision-makers in a seismically active country.