Influence of façade geometry on weathering

The results of extensive site observations of weathering patterns (defined as staining, discoloration, or the like) of building facades in a city environment are presented. A primary objective of the research is to determine the relationship between profile variations of precast concrete wall panels, water flow, and resulting weathering patterns. A comprehensive classification of panel shapes arranges panels with common shape characteristics and staining patterns. General categories of projecting frames, flush or punched openings, heavily sculptured, and plain types are analyzed with respect to both large-scale and small-scale staining patterns. An analysis of design details that influence staining patterns is included. Moreover, investigations for a preliminary mathematical model of water runoff over facade surfaces are also described. Finally, a number of pragmatic recommendations are established to guide panel designers.