When I submitted my application to be a Fellow in the American Institute of Architects, Jim Lawler, a great architect serving on Connecticut’s AIA “Fellows Committee,” had a critique of my application. “Well, it surely reflects your obsession with roofs,” he said.

For much of the architecture profession, flat roofs are something of an aesthetic obligation. To those outside the design intelligentsia, flat roofs long ago became a cultural cliché. To most “flat roof” = “Architect.”

All buildings must keep out the weather (or they are sculptures), so they have roofs. They’ve been called “The Fifth Façade.”  This phrase was coined in the late 1950s, referring to Jorn Utzon’s winning design for the Sydney Opera House. Utzon’s  sculptural “sails” of conically ascending roofs were the antithesis of the flat roofs prevalent in midcentury modernism and often caricatured in cartoons.

Ten years ago I gave a talk at an AIA conference on residential architecture and noted that I had reviewed all of the homes featured in last three years of Architectural Record’s Record House issues. I had determined that there might have been 3 houses that had pitched roofs (some had pitched features, others had hidden pitched roofs). The rest were “flat” (In contrast, 90% of the homes that are built to sell have traditionally pitched roofs.) A month later, at a different gathering, an architect pulled me aside and showed me a print-out sent to him by a junior editor at Record. “There are 5 homes with pitched roofs!” was the accompanying note (out of about 50 winners). Point taken, I guess.

In the last decade since, the magazine has featured, occasionally on the cover, pitched roofs for at least parts of some houses. But the vast majority are still flat-roofed High Modern houses. These distilled compositions of planes, voids, lines in orthogonal, right-angled boxiness, are so consistent as to be, for some of us, parodies of themselves. Sometimes an angle or a curve creeps in as counterpoint, but the careful rigidity is present as a baseline design criteria.

The vast majority of “serious” architecture receiving attention in architect-based publications uses that rectilinear approach. Yes, there are Hadidian sculpturalist expression of arcs, curves, warps. Some work is “cut,” skewed, or “fractal.” But the endless, overwhelmingly present datum to all of this expression is the carefully conspired, tightly composed, flat-roofed box-forms of “correct” architecture.

When I cite this extreme consistency in my writing, architects often confront me on my ignorance. “There are NO flat roofs!” they insist. Of course, water drains, so the flat ones do pitch. A little (usually to the interior of a building, over finished space); punctured by any number of vents and mechanical equipment. Correct modernist architecture has roofs surrounded by parapet walls of absolute straight coping lines, additively used to both disguise what lies behind them and define a visual “lid” on the building’s box.

And all of these roofs will leak more frequently than the traditionally pitched roof, which is the ancient solution to directing water away from both interior spaces and perimeter walls.

Let’s be clear: All roofs leak. Rain or snow (thank god) still falls in all climates. Some places have no snow, and very little rain, so flat roofs there have fewer liabilities and almost always cost less than the basic angled roof. As with all systems, there are now roof consultants who detail these necessary technical features (like curtain walls or mechanical systems).

But the flat roof stories of architect-designed houses are now memes. And the leaks aren’t just about the roofs: Frank Lloyd Wright’s Wingspread for the Johnson family famously leaked directly on the home’s first Thanksgiving dinner. Wright’s solution? “Move the table.” Frank Gehry’s kinetic sculptures have challenges, as did Louis Kahn’s roof of skylights over Yale’s Center for British Art.

But the aesthetic defendability of the flat roofed box in correct modern architecture has become as PC as any politician’s stump speech. Flat roofs can be visualized, understood, and drawn with direct aplomb. Making shapes that shed water is often harder. But at least architects try to make their flat roofs shed water. The hideous McMansion—with endless gables and dormers smashing into and out of each other—leaks like a sieve, too.

Every strip mall, every cheap commercial building, usually has a flat roof. Since most places of public accommodation require an architect, the leaking flat roof (dictated as much by cost as aesthetics) gets blamed on architects.

Conversely, to the architect intelligentsia, any whiff of pre-Modernist allusion to a pitched roof is derided as pandering mimicry. But who is mimicking whom? Cruise architect-focused media: the images predominantly feature flat-roofed buildings; look at traditional home media and a flat roof is seldom found.

In a world that seeks out and rewards reliable places that can be justified —whether it’s politics, music or food—the flat roof is an aesthetically “safe space” in Architectland. Except for the rest of us with an “obsession with roofs.”

In all of the new century’s cultural and professional changes, the flat roof may become more appealing than ever. Where once radicals gloried in rejecting the pandering banality of the pitched roof in favor of the “clean” box, now safely traditional Modernists hold onto the flat roof as validation of their professional credibility. To other architects at least.