The attractiveness and durability of stone claddings make them a common exterior finish. However, comparative research of the performance of long-lasting “dry fixed” stone claddings and those made using the “wet fixed” method has not yet been carried out. The objectives of this study are to (1) characterize the deterioration patterns of exterior dry- and wet-fixed stone claddings exposed to normal and marine environments; (2) evaluate the life expectancy limiting coefficient (modifying factors), and (3) quantify the influence of a marine environment on both cladding methods. The research methods integrate laboratory tests with the field survey and probabilistic service life prediction methods. The results of laboratory tests indicate that the compliance of the stone with the requirements of the standard does not assure the durability of the stone when used as an exterior cladding material in a marine environment. The findings of the probabilistic methods show that, in both normal and marine environment service conditions, the fixing method has a significant impact on the rate of the stone deterioration process and the long-term durability of dry-fixed stone claddings.