The present work deals with a unique in-service valuation of CSEB structures in Algeria. The inspection tries to bring out the impact of long time exposure under different and opposite climate and micro-seismic contexts. The diagnosis methodology is inspired by the approach largely adopted for the rehabilitation of traditional architecture. It involves the compilation of the previous survey reports, visual inspection of the structures, in-situ and laboratory tests to assess the residual CSEB mechanical properties. The CSEB constructions are located in the coastal north and the desertical south part of Algeria and were exposed respectively to a long-term Mediterranean and Saharian climate. The results of the investigation show that the CSEB in the construction located in the northern region is increasingly altered by the humidity. As the relative humidity rises, the fouling layers grow over some level. The surface pitting which is the consequence of long exposure to the wetting/drying cycles is also observed. The outer surfaces of the walls were honeycombed which reduce drastically the block resistance against the abrasion test. In some cases, differential erosion appears in the front of the walls, which indicates that the alteration does not proceed at the same rate from one area of the block to the other. However, owing to highly cementitious mortar used to join the earth blocks, the edges and corners remain unchipped. In the southern region where the arid climate dominating, the degradation of the CSEB is less prone to water attack but roughly exposed to the effect of the winddust frequent in this region and to the unawareness of the population. The paper presents also some recommendations to improve the earth construction durability with CSEB technique.