After hundred or thousand years of weathering, those distinctive building façade are very vulnerable to the changing environment and requires regular maintenance and preservation to keep it long lasting. However, In recent years, the investment in heritage conservation and renovation demonstrates an increasing tendency both financially and materially due to the climate change issues and the large amount of historic buildings. To better preserve those buildings is to understand how it deteriorated. Because of that we have to understand the characteristics of building materials and how they response to the environment. How the heat, air and moisture migrate in the building envelop and cause the deterioration in the façade? How different climate scenarios will impact the deterioration in building façade and how the climate change and future climate projection may influent the deterioration? . To make this projection convincing we have to do a large amount simulation to simulate various conditions until finally we build a large database and make a decision tree in a scientific and statistic way.