The obstacle course
Not culture, not taste, not weather. A stack of rules and habits, each reasonable-sounding alone, that together made the European default block impossible to build. Eight of them.
01
American zoning's founding move was to sort the city into single-use districts. Housing here, commerce there. On most of the American zoning map, an apartment above a shop — the single most ordinary condition in Berlin, Vienna, or Barcelona — is simply not a permitted use. The mixed block didn't lose a competition; it was defined out of the rulebook.
02
US rules commonly allow two or three stories — or, in small downtown pockets, a tower. The band in between, five to seven stories at the sidewalk, is precisely where the European street wall lives: Berlin's Traufhöhe, Vienna's Gründerzeit cornice, the Paris boulevard. Call it the missing middle of height, not just of unit count.
03
Require one or two stalls per home and the middle of the block becomes a garage. The courtyard turns into a podium deck over parking; the ground floor becomes a ramp and a lobby; the sidewalk shrinks to feed curb cuts. Where minimums have been repealed — as California has done near transit — the courtyard becomes geometrically possible again.
04
Front setbacks turn street walls into front yards; side setbacks slice the block into leftover strips no one uses. The European block inverts the diagram: build to the lot lines at the street, and pool the open space into one shared Hof in the middle, big enough to be worth something.
05
American egress practice long required two enclosed stairs for buildings above a few stories, which pushes designs toward deep slabs with a sealed hallway down the middle. The single-stair, gallery-access mid-rise — the social heart of La Borda and R50 — was effectively illegal in most US cities. That is changing: several states have recently moved on single-stair reform, and the conversation is live in California. It is a code research item, not a fantasy — the current state-by-state picture, and what to do with it, is in the plan.
06
A Berlin or Vienna sidewalk is a designed room: wide enough for café tables, tree pits, bicycles, and two prams passing. Many American sidewalks are whatever remains after travel lanes and street parking are drawn. The type needs its front room back.
07
Lenders and appraisers underwrite what they can compare: "garden apartment," "podium wrap," "high-rise." A 40-unit limited-equity courtyard co-op with shops has no product box, so it reads as risk regardless of its actual economics. And a developer's profit wants sellable condos, not a Hof — which is why the European examples are almost all resident-led, with the developer's margin folded back into the building.
08
Not magic culture. A height cap that produces a continuous cornice line; perimeter blocks that enclose Hinterhöfe; trams in the street; ground-floor commercial as the unremarkable default; buildings that enclose space instead of sitting as objects in parking. Every one of those is a rule or a habit — and rules can be rewritten. Once the type is visible, the question stops being "what if we invented a new way to live?" and becomes "why not this lot?"
So: why not this lot?
The Berkeley proposal →