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The durability of concretes from the precast industry was studied in environmental conditions simulating wetting/ drying in a natural acidic environment. The industrial concretes were dry concrete and fluid concrete, both having cement content of 265 kg/m3. They were compared with conventional concrete of 360 kg/m3 cement content, with all the concretes studied having the same water/cement ratio of 0·47. Ageing in the mild acidic environment did not result in any detrimental effect and in some cases even a positive influence was observed. These differences were discussed in terms of the micro-structural observations. The strength was largely independent of the type of concrete, reflecting their similar water/cement ratio. However, permeability and performance with regard to carbonation and chloride penetration was significantly better in the industrial concretes, and this was attributed to their lower cement content. This trend suggests that the current standards that set the requirements for minimum cement content for durability should be revisited.