The Caribbean coast has been the location of the main tourist development in Mexico in recent years. To cope with the massive population that provides services in the tourist region, many housing developments have been built with government assistance. The main structural system employed in these houses combines masonry walls–made from concrete block and confined by reinforced concrete tie columns and bond beams–, with reinforced concrete slabs used for roofing. The aggressive environment, due to the closeness of the Caribbean Sea, has provoked severe damage in the concrete elements of the houses in a short time. In this study, two housing developments were studied, one located near Cancun, and the other located in the State capital. Concrete properties, as well as chloride concentrations and carbonation depths, were measured from concrete cores obtained from the houses. It was found that the environment is highly aggressive, thus the housing infrastructure built in this region is continually affected, with heavy losses due to corrosion of the reinforcing steel embedded in concrete. However, bad construction practices are also accountable for the damage observed.