Exterior surfaces or faces of a building that are substantially in one plane, particularly those perceived to be the principal or most architecturally ambitious ones, designed with special regard to their conspicuousness or association with an entrance and looks onto a street or open space. For the external areas of buildings, potentially including the facade and other features, but not necessarily restricted to surface features, use "fronts (architectural)." For the vertical arrangements of exterior or interior features, use "elevations (building divisions)."

Source: AAT

http://vocab.getty.edu/page/aat/300002526