This book introduces a maintenance model that will assist decision-makers in their choice of building maintenance policies.The model is stochastic and condition-based that analyses the impact of different maintenance strategies on the durability and performance of different buildings envelope elements (facades, windows, and roofs).  As non-structural elements, the maintenance of buildings envelope can be disregarded stakeholders. However, as first barrier to the external environment, these elements are critical to buildings' overall performance and are expected to meet aesthetic, comfort,...