A computational analysis aimed at increasing service life of exterior thermal insulation systems suitable for building envelopes based on autoclaved aerated concrete (AAC) in the climatic conditions of Central Europe is presented. In the first step, a sensitivity analysis of the effect of hygric parameters of materials involved in thermal insulation systems on the hygrothermal performance of AAC envelopes is accomplished, in order to identify appropriate ranges of their values. Computational simulations of temperature and moisture fields in AAC building envelopes are then performed, using proper combinations of properties of exterior layers. The results are evaluated from the point of view of frost resistance of the whole building envelope, and the appropriate values of hygric properties of thermal insulation layer and exterior plaster are identified. Finally, prospective types of materials suitable for the investigated thermal insulation system are proposed. (C) 2011 Elsevier B.V. All rights reserved.