Roof effectiveness is determined most by its pitch and shape, next by its detailing, next by its materials, and last by its look, which is irrelevant. Architects who have indulged Post-Modernism’s penchant for pitched roofs—all those triangular gables, even on top of skyscrapers—have been startled to discover that these roofs work better than what they’re used to. That’s because what three generations of architects are used to is flat roofs.
