The Browser newsletter republished my latest essay on how to build a fine-grained city. Fine-grained apartment blocks need 1) medium-sized parcels (NOT TOO SMALL) and 2) a legal system that allows buildings to meet at the side property line—through party walls, fire walls, or rules allowing two independent walls to abut. We built cities this way for thousands of years, when we were poorer and far less technologically sophisticated. Then we layered on side setbacks and administrative complexity that made fine-grained urbanism much harder to produce. The question now is whether AI-enabled development and planning systems can help us recover that capacity and make small, contiguous apartment buildings practical again. You can read the essay free on my Substack.

Built more than 100 years apart, the Greystones of Jackson Heights and Park Kennedy in Washington, D.C. show what we have lost in American urban development ... the capacity to CHUNK floor area into multiple contiguous properties. The Greystones, built in 1917–18, are 14 separate five-story apartment buildings. Each occupies its own 63'x100' lot (this is a great lot size). Yet they touch one another to form a continuous blockfronts, with their rear open spaces joining into beautiful block-long gardens. The Greystones of Jackson Heights is simultaneously one coherent place and many buildings. And the buildings themselves are fantastically simple. The Greystones were designed with 2-3 apartments per floor, organized around a central stair. The apartments extend from street to garden, giving them light and exposure on both sides. They are spacious, efficient homes produced with very little circulation devoted to hallways. No long corridors. Residents share a landing with essentially one other household. No costly structured parking or amenity decks driving up per bedroom costs. Compare that with Park Kennedy, built a century later. Park Kennedy is a good contemporary building, but it consolidates 262 apartments and retail and amenity space into a single, $95M development ... with a grand atrium, rooftop deck, fitness and yoga rooms, game room, lounges, coworking library, conference center, dog run, concierge and other private amenities. The Greystones represent a fundamentally different urban economics. You don't need the apartment building to be the amenity when the neighborhood itself is the amenity. Instead of paying (in rent or purchase price) for enormous internal circulation systems and elaborate private amenity packages, residents can have efficient, compact point-access buildings, spacious dual-aspect homes, beautiful shared gardens, and then step outside into an extraordinarily rich neighborhood. And critically, that neighborhood does not have to be owned by the same entity. Even though they were built by a single developer, the Greystones are separate properties, on distinct tax parcels, with separate ownership identities and entrances, while still forming a single continuous urban composition. Park Kennedy simulates the appearance of many buildings within one enormous building. It's actually an impressive imitation of a fine-grained block. But Jackson Heights shows how you can have real granularity beneath the surface. And get the neighborhood for free, because it passively emerges from dense, mixed-use apartments that are affordable enough for a broad demographic to live there. That lost capacity matters for affordability, development participation and the quality of urban life. Jackson Heights is just one example ... there are many contemporary examples in Europe, where cities use parcelization to avoid large housing blocks and preserve granularity, medium scale, diverse ownership, and yard area WHILE maintaining the density needed for neighborhood vibrancy. Because when you build dense, mixed-use fine-grained blocks, the neighborhood itself is the amenity.