How cities have become a grey area When urban design doesn’t break the rules, but learns how to use them

The contemporary paradigm seems to operate through minimal variations: changing just enough to produce effects, but not enough to step outside the normative perimeter. It is a logic that cuts across different fields, from designer drugs, where small alterations in structure produce formally new substances, to cities, where seemingly legitimate transformations progressively redefine uses and functions. Contemporary society seems to have learned to design everything within the margin, in the fold, at the point where the rule exists but is not yet sufficient to govern what is happening.

The contemporary city, in many cases, works in the same way. It is not necessarily transformed through explicit rupture, but through a series of formally legitimate micro-shifts. A house remains a house, but it can become a financial product. An apartment remains habitable, but it can be optimized for tourist turnover. A neighborhood remains “regenerated”, but it does not always remain truly available to those who lived there before. The issue, therefore, is not only who designs cities, but for what kind of value they are designed.

A reassuring urban lexicon

In recent years, the urban lexicon has been filled with reassuring words: regeneration, valorization, attractiveness, functional mix, district, hub, experience. These are useful terms, often necessary, sometimes sincere. But they are also highly elastic words. They can indicate a real improvement in urban quality, or they can become the elegant vocabulary used to describe an increase in real estate value. The problem is not transformation itself. Cities have always changed. The point is to understand when change produces livable space and when, instead, it primarily produces return.

The UN has used a precise expression for years: “financialization of housing”. It defines it as the moment when housing is treated not primarily as a social good, but as a commodity, that is, as a vehicle for wealth and investment. According to the OHCHR, global real estate represents nearly 60% of the value of all global assets, with residential as the dominant component. This is an enormous figure because it changes the scale of the discussion, placing housing within financial circuits far larger than the everyday lives of those who inhabit it.

From this emerges the urban gray zone. It is not necessarily an illegal space. It is a space designed to be compatible with existing rules, but not always with the right to the city. A transformation can comply with regulations, permits, land-use designations, and administrative procedures, and at the same time contribute to making a neighborhood less accessible, less mixed, less livable. This is where design stops being only architecture or urban planning and becomes a regulatory strategy: not building against the system, but precisely within its loopholes.

The financialized city

The most recent European data helps clarify why this is no longer just a theoretical issue. According to Eurostat, in the fourth quarter of 2025 housing prices in the European Union increased by 5.5% compared to the same period of the previous year, while rents rose by 3.2%. Over the long term, between 2010 and 2024, rents in the EU increased by 25%. The European Commission also notes that since 2013 housing prices in the EU have grown by over 60%, while average rents have increased by about 20%, with stronger pressure in urban areas.

The financialized city does not function as a single event. It does not arrive all at once. It settles in layers. First, the potential value of an area increases, then the type of activities that can afford that space changes, followed by its inhabitants and the language used to describe that neighborhood. At a certain point, what was ordinary becomes lifestyle. The bakery replaces the local shop, the bar becomes a specialty coffee, and the studio apartment becomes a flexible unit. It is not always a loss. Sometimes it brings better services, maintenance, safety, new economies. But the question remains: who can remain within this improved version of the city?

The example of short-term rentals is one of the most evident because it makes an otherwise abstract transformation visible: when thousands of individual choices follow the same economic convenience, the city changes function. A condominium staircase can become a distributed reception, a neighborhood can become a sequence of check-ins, a lock can become tourist infrastructure.

“Hotel Cities”

Milan, from this perspective, has become a symbolic case also through very small objects. Keyboxes, those small containers for keys linked to autonomous check-ins, have been at the center of a local measure ordering their removal from public spaces. It is interesting because the keybox itself is an almost banal object. But precisely for this reason it works as a symbol: it is not a skyscraper, not a masterplan, not a spectacular infrastructure. It is a small metal prosthesis that tells the story of a city in which even access to an apartment becomes part of a broader economic chain.

Barcelona has taken an even more radical approach, announcing in 2024 its intention to eliminate tourist apartment licenses by November 2028, in a plan designed to contain housing costs and make the city more livable for residents. Here too, the point is not to create a simplistic opposition between tourism and residents. Tourism is economy, work, imagination, and exchange. But when it becomes the dominant function of entire parts of the city, the balance breaks.

This distinction is fundamental. The city is not a larger hotel. It is not a catalog of experiences. It is a fragile structure made of permanence, habits, conflicts, proximity networks, invisible labor, idle time. A city lives also thanks to everything that does not immediately produce economic value.

Do public spaces still exist?

The gray zone, however, does not only concern housing. It also concerns public space. In many contemporary cities, the boundary between public and private has become less legible.

This is where design becomes political even when it appears neutral.

The financialized city is not necessarily an ugly city. Often it is clean, photogenic, well-lit. The point is that aesthetic quality does not automatically coincide with urban quality.

For this reason, the term “regeneration” must be used carefully.

Toward an ideal city

The point, therefore, is not to oppose every private investment, nor to imagine a frozen city. If a city works only for those who visit it, buy it, or monetize it, then it is no longer truly a city. It is a spatial platform.

The gray zone city is not illegal. It is harder to criticize precisely because it is often perfectly legal, authorized, narrated through the language of progress.

Perhaps the real urban issue of the coming years will be precisely this: learning to read what remains formally correct but socially problematic. The contemporary city is not always designed against rules. Much more often, it is designed within their folds. And it is there, in that gray zone, that we need to look again.