The building's exterior -- the "skin" of the building -- was one area where design needs and economy could mesh. Three different materials were used. Standard, economical precast concrete sufficed where support was not an issue. On the cantilevered arches at the lake elevation, where weight had to be minimized, Findorff used lighter-weight glass fiber reinforced concrete. The soffits (the horizontal area under overhangs) are faced with an exterior insulation and finish system that has the advantages of being lightweight, flexible enough to withstand building movement and seasonal temperature fluctuations, and economical. "Every decision we made was guided by what we call value engineering," says Lynch. "It meant working with engineers and architects to analyze different components, systems and structural strategies to present the best return for the user. You want to implement the most cost-effective building technology so more of the budget can be spent on the building finishes and internal amenities people will actually see and use and enjoy."