The House of Michaelerplatz is Loos' most famous building, and – though it is hard to see now – at the time, his most controversial. One of the first modern office buildings in Vienna, the steel concrete construction provides wide structural spans with flexible space use. (The marble pillars across the storefront entrance are not load-bearing.) The building occupies a commanding position opposite the imperial Hofburg, and provides four stories of apartments above the business floors. The business floors were originally a gentlemen's outfitter, but are now a bank. The facade of the lower stories is quite ornate, chiefly through the rich, green Cipollino (Greek) marble. Inside the business floors are opulent through the richness of their materials, contrasting a modern minimalism in the detailing. The controversial part of the design was the bareness of the undecorated white facade of the higher, residential stories. Construction was even stopped in 1910 in reaction to the simplicity of these floors. The flower boxes were a compromise form of decoration to resolve the dispute.