Upscale buildings around this time in the last century had a Classical bent. The architecture of the Renaissance, meaning that which copied the Greeks of 2,500 years ago, remained in fashion for a very long time. Even today we have new structures coming up which have the pediment (the triangular structure first seen on top of the Parthenon). Porticos and façades very often have columns in the three Greek orders: Doric (the flat ones), Ionic (with scrolls) and Corinthian (the most floral). Of course these columns were made of stone.
And then in America, architects began to discard such styling as