The use of thin marble and limestone panels for facade cladding has increased substantially during the last five decades. The durability of such thin slabs (often only 30 mm thick) has been assumed to be satisfactory based on centuries of successful use as a structural building stone. Nevertheless, all over the world, the long-term deformation and strength loss of some cladding panels have led to concerns about its safe and durable use. The detailed assessment of marble and limestone within the TEAM-project (see also www.sp.se/building/team), is used to develop a hypothesis for the observed deterioration and to develop remedial actions. This paper presents test methods for the bowing and expansion potential of marble. The method is discussed and the relevance of the test exposures is demonstrated by comparisons with on-site observations on marble cladding. A number of results are presented, illustrating the influence of the temperature cycles, the humidity and the stonetype on the bowing and expansion.