China builds towers in a park, while America, and nearly everyone else, builds squat mid-rise blocks. The difference comes down to regulation, not culture.
Inasmuch as people think about differences in urban form between countries, they tend to assume these are a matter of ‘culture’, either of buyers, architects, or developers. And sometimes, this is true. For example, most English urban developments in the nineteenth century were terraced houses, whereas most Scottish ones were flats, though there were no laws requiring this and though the two countries were similarly wealthy.
But very often, differences in urban form are the result of regulation. This has become increasingly true over time, as it has become increasingly common for rules to constitute the binding constraint on built volume. Today, it is frequently the case that the built form of a neighborhood can be predicted with almost algorithmic accuracy from the regulations that it is subject to.
If culture plays a role at all, it is through shaping regulation, not through shaping consumer preferences. But even this can be overrated: building regulations are technical documents written by tiny groups of professionals, and the same background culture can often coexist with a wide range of different regulatory systems.
We can understand this by looking at the cities of the world’s two leading economies, China and the United States. The cities of China and the United States look very different. The tall residential towers typical of Beijing or Chongqing have little in common with the squat mid-rise apartments preferred across the United States, in those cases where the US does build apartments rather than single-family homes.
It is natural to assume that there is some ‘deep’ cultural explanation for this. But it is not clear that this is so. In fact, US apartment urbanism is closer to Hong Kong, Taiwan, and Macau than Chinese apartments are. Rather than reflecting consumer preferences or a unique aesthetic heritage, the answer seems to mostly come down to zoning rules and building codes.
Back to basics: understanding floor area ratio
High-rises are new to China. Few were built until the economic and urbanization boom of the 1990s, but since then, they have become the standard Chinese home. In 2015, half of the population – including most people in urban areas – lived in a high-rise. Today, that percentage continues to grow as more people move from the countryside to cities.
In contrast, apartments comprise only a small portion of the US housing market. Two thirds of all homes in the US are detached dwellings, and most have been around for a while; the average home in the US is over 40 years old. However, in large cities, where land is scarce, most new residential structures are apartments – comprising, for example, 75 percent of all new homes in the Bay Area. Of those new apartments, most are in large mid-rise buildings.
Despite their strong visual dissimilarities, new construction in China and the US share one basic feature: they each support roughly the same population density, as their floor area ratio is similar.
The floor area ratio, or FAR, is calculated by dividing the area of all of a building’s floors by the area of the entire parcel of land the building sits on, including any internal roads. It is the measure of how much building there is in a given space, a measure of built density.
Population density and the density of dwellings per acre or hectare are both useful metrics. But pro-housing advocates should not take them as objectives because both of them can be achieved by cramming more people into the same amount of floorspace or subdividing the same amount of floorspace into smaller dwellings. FAR just measures how much usable floor space there is on a given plot or development. It can be split into dwellings based on population demand and income.
Zoning regulations typically rely on gross FAR, which includes all indoor above-ground space, in contrast to net FAR, which only includes the apartments themselves and excludes hallways, lobbies, or other service spaces.
When it comes to city planning, a building’s height is not always a good measure of its density: a short building that covers a whole lot can have the same amount of indoor space as a tall building that only covers part of a lot. For example, a single-storey building that covers an entire lot has a floor area ratio of 1.0, but a two-storey building that covers half the lot would also have a floor area ratio of 1.0.
Typical floor area ratios range from 0.1 for single-family homes built on half-acre lots to 12, indicating high-rises of 30 stories or more, of the type only found in populous downtowns. (The Empire State Building has a floor area ratio of 31, but this sort of density is rarely economical or permitted.) This has profound implications for the features and amenities of a neighborhood. The exurban density of FAR 0.1, for example, means that residents almost always rely on cars for transportation, as there aren’t enough people to support public transit or any sort of business within walking distance.
In between these two extremes are a range of other housing types.
- A density of FAR 0.4 forms the backbone of the classic American suburb: houses with front, back, and small side yards, possibly linked up to the urban center by basic transit on the order of a single bus line.
- FAR 1.5 indicates row houses and garden apartments – think of the less-dense neighborhoods in Brooklyn, Richmond in London, or the terraces of the Hague and Copenhagen. Generally served by more robust public transit, as traffic congestion is a given, usually, there is a variety of retail within walking distance or a short ride away on public transit.
- FAR 4.0 is the density at which mid-rise apartment blocks or high-rise towers appear. It is difficult for everyone to live at this density and yet rely on cars for transport, as it would require setting out unaffordable acres of tarmac for parking and to accommodate all the traffic. Good public transit is a must, and retail serving residents’ daily needs is all within walking distance.
How the world builds
The world has not converged on a single way of building flats. Spain, for example, extensively uses mid-rise centralized greenfield development: new neighborhoods are built at the edge of the city and typically feature buildings five to ten storeys tall wrapped around a central courtyard. These buildings’ floor area ratio falls in the 2.0 to 4.0 range.
South Asia, meanwhile, commonly employs mid-rise decentralized greenfield development, consisting of gridded streets with small lots that are sold off to individual buyers, who build properties one at a time. Parts of the outer boroughs of New York were built this way as well: the subways were first extended into farmland, which was then developed into mid-rise buildings. The resulting floor area ratio of this type of development can be high – around 3.0 to 6.0 – since buildings cover the entire lot and there are no central courtyards.
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This is an example of mid-rise decentralized greenfield development, which is common in South Asia. In this example, the upper left has been fully built up, while the lower right has some lots developed and others yet to be built on.
In Latin America, Japan, and present-day New York City, infill high-rise development in residential neighborhoods is more common. This model predominates in places where regulatory or geographical barriers, such as water and mountains, make new greenfield development difficult. High-rise buildings are constructed one at a time in existing neighborhoods; developers often buy up adjacent buildings to get a large enough site, typically at least 100 by 100 feet. Individual buildings normally have floor area ratios of 10.0 or more, although development is incremental, and only some lots are developed up to this density.
Canada, meanwhile, often employs infill high-rise development of commercial property, redeveloping large commercial lots, such as shopping centers, into one or two enormous high-rises. These redeveloped buildings often have extremely high floor area ratios, but the average density of the city remains low because, with the exception of lots bordering major streets, the remainder of the land consists of low-density suburbs.
The US rediscovers the mid-rise city block
Until the 1950s, US city planners tended to follow the South Asian model, dividing land into a grid of blocks, which were then subdivided into narrow rectangular lots sold to individual buyers. One of the most common lot sizes in New York City, for example, was 25 feet wide and 100 feet deep. The classic tenement buildings built on such blocks all followed the same basic design: built out of brick – required by fire safety regulations to stop fires from spreading to adjacent buildings – the tenements rose five to six stories high to meet height regulations as well as handle the lack of elevators, which were uncommon until the late 1800s. The buildings filled most of the lot to maximize the amount of indoor space, with a small, zoning-mandated rear yard and narrow, mandatory light wells providing windows into interior rooms.
Tenements and similar buildings were plagued by a range of problems, including overcrowding, fire hazards, and poor sanitation. While many of these issues were not necessarily caused by the buildings’ design – low incomes meant entire families would live in a single room – they often became associated with it.
As a result, tenement reformers of the late nineteenth and early twentieth centuries advocated for buildings to be constructed with more windows and larger yards – campaigns that were often rooted in Victorian-era concerns about the evils of ‘foul air’, which was believed to cause infectious disease. One disease in particular, tuberculosis, played a significant role in reshaping urban architecture. In the absence of modern antibiotic treatments and vaccination, the prescribed treatment was sunlight, fresh air, and rest. Patients recuperated in purpose-built sanatoriums outfitted with large south-facing windows and porches.
This sanatorium architecture, with its emphasis on natural light and airy spaces, went on to influence mid-twentieth-century residential design. Apartments built as part of the Modernist movement were freestanding structures with large windows, balconies, and spacious yards between buildings. To make space for yards without sacrificing density, buildings became taller, creating the ‘towers-in-the-park’ design that became the signature of government-funded public housing projects between the 1950s and 1970s.
But taller structures incurred new costs. Compared to low-rise buildings that filled the whole lot, tall buildings with large yards required more maintenance: grass that needed to be mowed in the summer and paths that needed shoveling in the winter. Tenements and row houses relied on stairs, but towers needed elevators. Such maintenance was problematic for underfunded public housing projects in particular. The yards also presented a security challenge since anyone could enter them from the street. By the 1970s, tower-in-the-park designs had fallen out of favor, and over the remainder of the twentieth century, many were demolished and replaced with low-rise buildings.
Throughout the twentieth century, Americans moved to the suburbs in droves: from the 1930s onwards, the percent of the population living in central cities has held steady at around 30 percent, while the percentage living in suburbs grew steadily from 10 percent to over 50. But suburban sprawl brought with it a host of environmental and traffic problems, including long commutes, air pollution, and loss of open space. In response, the ‘New Urbanist’ movement of the late twentieth century sought to make the city a desirable place to live again. To escape the negative associations of the Modernist towers, New Urbanism advocated for mid-rise housing.
To help overcome local opposition to new construction, these buildings are often styled to look like housing from the 1800s, with design features such as classical columns, ornament, sloped roofs, brick, and wood siding on the exterior. To further soften visual and shadow impacts, zoning codes often require buildings to step down in the back or to the side when there are existing houses next door.
While the New Urbanist mid-rises might have looked like an 1800s block on the outside, a century’s worth of changes in building codes, transportation infrastructure, the finance industry, and construction industry norms meant that they differed substantially on the inside.
For one thing, twentieth-century buildings tended to be larger. The International Building Code (IBC), the standard building code adopted throughout the US in the 1990s, required two staircases for any apartment building with more than three floors or more than four units per floor. This made smaller buildings impractical, as stairs would take up too much space.
For another, parking had to be taken into consideration. By the late 1990s, approximately 90 percent of US households owned at least one vehicle, and many cities required one or more parking spaces per apartment to avoid competition for street parking.
For a third, the residential construction industry had shifted to building most suburban houses and apartments using light wood-frame construction, which reduced construction costs by as much as 20 percent to 30 percent compared to the brick or concrete more commonly used in nineteenth-century mid-rise housing. Finally, these newer structures favored mechanical rather than window-based ventilation, meaning that windowless bathrooms, kitchens, and bedrooms, which were not permitted in the nineteenth or early twentieth centuries, became more common.
All of these changes led to the prevalence of the 5-over-1 design, which maximizes the amount of apartment space that can be built on a site while still being economical to build. This style of building is common in infill developments in major cities on both coasts, as well as across the American South, where it includes a variant known as the Texas Doughnut that puts the garage in the middle of, rather than under, the apartments.
What’s in a name? ‘5-over-1’ and ‘four plus one’
The term ‘5-over-1’ is often assumed to refer to the number and type of floors a building has: five residential floors above one ground floor used for retail or parking. But in fact, the term was initially used by architects and code officials to refer to the building’s construction and materials.
The US building code classifies construction materials and methods into five basic types:
- I. Noncombustible – Concrete or steel covered with fire protection
- II. Noncombustible – Unprotected steel
- III. Noncombustible exterior only
- IV. Heavy timber or mass timber
- V. Wood frame
The term ‘5-over-1’ originally referred to a mid-rise apartment building with Type V wood construction above Type I concrete. The wood upper floors held the apartments, while the concrete first floor, also known as the podium, contained parking or retail space.
This stacked design dates back to the 1960s, when parking requirements in zoning codes mandated a full floor of parking for a mid-rise apartment building. These first-floor garages were built from concrete since wood cannot support the wide spans required for convenient car storage. But as the term became more widely adopted, it came to refer to the number of floors and their use. In Chicago, for example, 1960s buildings of this style are called ‘four plus ones’ because they consist of four floors of apartments over one floor of parking.
By the 1970s, further increases in parking requirements made even a whole floor of parking insufficient. Instead, developers began building structures that wrapped apartments around a multi-level parking garage – known as Texas donuts or wraps – or built low-density garden apartments in the suburbs instead.
Then, in the 1980s and 1990s, US cities made additional zoning changes that reduced parking requirements in downtown areas, based on the principle of New Urbanism, in order to promote walking and public transportation. This once again enabled a single garage floor to provide enough parking for four floors of housing. This change coincided with the standardization of regional building codes into the International Building Code now used in all 50 states, setting the stage for the 5-over-1 design to spread nationwide.
As urban living returned to popularity in the 21st century, this type of apartment building began to appear in large numbers in downtowns across the country. In the Midwest, for example, apartment buildings of 50 or more units (both mid-rises and high-rises) went from comprising less than 20 percent of all new apartments to over 60 percent between the early 2000s and the early 2020s. Such buildings made efficient use of land and offered many features that made them more desirable than older buildings or suburban houses, including on-site amenities like gyms, pools, and recreation rooms, secure on-site parking, and close proximity to retail and entertainment.
Challenges and detractors
Despite their increasing popularity, however, 5-over-1s were not without their opponents. Outside of urban downtowns, their height – while significantly shorter than towers in the park – irritated locals, who complained to city councils that they would overshadow nearby two- and three-story houses. Some found fault with their design and with gentrification as a whole: since zoning had made residential areas off-limits to apartments, these buildings often replaced retail buildings, accelerating the changing character of neighborhoods’ main streets.
There are also more practical reasons for 5-over-1s’ unpopularity in some quarters. Because the buildings can’t grow taller – either due to building code limits on wood frame construction or zoning height limits to preserve residents’ views – growing demand has made these buildings ever wider. As a result, an increasing number of units can only face in one direction, which means that windowless rooms have become more common. Furthermore, the double-loaded corridor design, with apartments on both sides of a hallway, makes it harder to allow for three-bedroom or larger apartments except at the building’s outer corners. Inside corners pose an even bigger challenge, necessitating triangular units with a single tiny window. Some developers have gone one step further and designed units with windowless bedrooms.
A further challenge is that the ground-floor retail spaces of 5-over-1s can be hard to lease since they’re often oddly shaped to fit around parking, stairs, and other service spaces. And five floors of apartments don’t house enough people to support a whole floor of retail: a two-person household living in a 600-square foot apartment only creates demand for ten square feet of urban retail. Another issue is that many large-scale 5-over-1 developments are located in former industrial areas with little or no preexisting retail traffic or destination retail. Retail developers must therefore change people’s perceptions and habits to draw a clientele, which takes time. For example, it took about 12 years before retail spaces started to fill in San Francisco’s Mission Bay neighborhood.
Despite the popularity of 5-over-1s, then, it’s fair to say that the US is still searching for its ideal urban design. The 5-over-1 works for people in small households who are okay with limited sunlight and open space, but if urban living is to become more common, more options will be needed to appeal to a wider population.
China’s preferred development style: the xiaoqu
In contrast to the mid-rises that abound in US cities today, Chinese cities favor what is known as the 小区 (xiaoqu) or microdistrict. These tower-in-the-park-style residential developments comprise several high-rises on roughly 15 to 20 acres, surrounded by wide arterial roads.
A notable difference from the mid-twentieth-century US tower-in-the-park design is that xiaoqus are built as gated communities. While primarily residential, the microdistricts also provide stores and services for residents, including schools and other infrastructure. However, they do not contain offices or industry, and retail is limited to neighborhood-serving services, such as convenience stores and restaurants.
Because Chinese building codes require that all units get direct sunlight, apartments are south-facing, with taller buildings located towards the north side of the microdistrict to minimize shadows on other residences. The sunlight requirement results in large spaces between buildings, limiting the floor area ratio to around 2.0 to 4.0, even for high-rises. Adding more floors only slightly increases the density, as taller buildings need to be spaced further apart to meet the sunlight requirements.
China’s building code also requires that 30 percent of the development’s land must be devoted to green space. As a result, xiaoqus feature a large amount of garden space – a selling point that sets them apart from older developments. In the 2000s, when the developments grew popular, developers would market their housing as ‘like living abroad’, giving them US- and European-inspired names and designs.
The Chinese microdistrict evolved out of the collective-era 单位 (danwei), or work unit, which was itself based on the Soviet mikrorayon, or microdistrict. Under Soviet planning standards, each microdistrict housed 9,000 to 12,000 people and included schools, basic shopping, and other daily-use facilities within 400 meters of each home. Chinese xiaoqus are smaller, containing around 2,000 households.
Built between the 1950s and 1970s to house factory workers, danwei neighborhoods consisted of rows of mid-rise buildings and provided facilities such as schools and community centers on-site. As part of the economic reforms of the 1980s and 1990s, danwei housing was privatized, and the apartments were sold to residents, often at a low cost (similar to the British policy of Right to Buy under Margaret Thatcher).
The design of these communities can be described as Soviet site plans with Chinese characteristics. Soviet-style housing was laid out along the perimeter of a block, with a large courtyard in the middle (unlike typical modernist row or slab blocks); in contrast, Chinese danwei buildings were arranged in rows, with all apartments facing south and buildings spaced apart so that south-facing windows weren’t shaded. Initially this reflected a longstanding preference (grounded in traditional feng shui geomancy) for south-facing dwellings: Chinese houses built before the twentieth century traditionally faced south for protection against cold winter winds from the north as well as summer heat from the afternoon sun in the west. Today, with rising rates of car ownership – there are now 50 cars per 100 urban households in China – the space between buildings is used for parking.
Another type of housing built in China in the mid-twentieth century was the 筒子楼 (tongzilou), or tube building: a dormitory-style walkup with individual rooms and communal kitchens and bathrooms lining a long hallway. Tongzilou buildings had two main layouts: an indoor hallway with rooms on both sides and an open balcony-style hallway with rooms on one side.
In the later twentieth century, as population growth and rising standards of living spurred the government to build more housing and set aside more space for individual apartments, the dominant design shifted to rows of single-point access blocks: buildings of generally up to six stories built around a single stairwell, with three to four apartments sharing each stairwell. Multiple buildings were linked together to create larger buildings. This layout maintained the practice of giving all residents a south-facing room. The earliest high-rises built in Beijing and Shanghai – predecessors to the xiaoqu – also used this design, adding an elevator next to the stairs. Like other building designs, the spacing of these towers was defined by China’s direct sunlight requirements.
Illuminating the direct sunlight requirement
Of all Chinese building regulations, the direct sunlight requirement has had the greatest impact on the design of housing, determining not only the design of new housing but also the population density of a city, with southern cities being denser.
Modern sunlight guidelines in China date back to 1993, and were created in response to more tall buildings being built. The guidelines specify the number of hours of direct sunlight on a certain day that a given residential building must receive based on the regional climate and local population. For example, a building in climate zone II – somewhat colder areas in the north such as Beijing – must receive 2 hours of sunlight on 大寒 (Major Cold Day), January 20, if it’s in a city with 500,000 or more people, and 3 hours if in a city with less than 500,000. A building in climate zone V – temperate areas like Kunming and Guiyang – must receive more than one hour of direct sunlight on the Winter Solstice, December 21.
Most Chinese people live in climate zones I, II, III, and IV and live in cities with more than 500,000 people. As a result, the most common standard is two hours of direct sunlight on 大寒 (Major Cold Day), January 20. Buildings in the warmer climate zones often do not have heating, which may explain the increased winter sunlight requirements. (It is also easier to meet any given requirement for winter sun in these zones as the angle of the sun is always higher in the sky than up North.)
Why is sunlight given such importance in Chinese building regulations? There are practical reasons: direct sunlight is useful for drying clothes – even today, very few households in China have dryers, even though consumers can now afford them – and helps keep homes warm in winter. Homes with more sunlight are also more desirable; one study found that south-facing Shanghai apartments sold for 7.2 percent more than north-facing apartments.
That said, neither of these rules have passed over to other countries with large populations of people of Chinese descent, such as Macau, Hong Kong, Taiwan, Singapore, and so on, where towers in the park exist but jostle with courtyard blocks. Nor is it evident in common unregulated low-end construction – called urban villages – which suggests that it is regulation that has made it such a salient feature in Chinese urbanism.
The sunlight requirement is one reason why American-style development wouldn’t be feasible in China. In American-style apartment blocks, under half of homes face south. US apartments also have other features, like windowless kitchens and wood-framed construction, that would be unfeasible in China, where building codes require kitchens to have windows, and wood is a more scarce, and therefore more expensive, building material.
One major consequence of the sunlight law is that it has effectively put an upper limit on density in Chinese cities. In the south, the sun is at a higher angle during the winter, which means that buildings can be spaced more closely together while still allowing enough direct sunlight to reach the lower floors. As a result, southern cities such as Guangzhou are about 50 percent denser than northern cities such as Beijing. (This mimics the pattern across Europe, where Sicilian, Southern Spanish, and Greek cities have had the narrowest streets since medieval times and Northern European cities the widest.)
In southern China, the sun is at a higher angle during the winter, allowing apartments to be built more densely. In the north, buildings must be spaced further apart.
Building up and out: the birth of modern high-rise
Modern high-rise construction in China began in the 1990s in response to policies designed to preserve farmland by building up instead of out. Following economic liberalization in the 1980s, the central government became concerned with a decline in farmland caused by real estate development and implemented the 1987 Land Utilization Plan. Previously, land use planning had been left up to local governments. Under the 1987 and subsequent plans, the central government set limits on how much farmland could be converted to urban use.
This meant that US-style suburban sprawl was off the table. While developments of detached houses do exist in China – often marketed as villas – they are limited to the very rich.
In creating the modern xiaoqu, Chinese city planners looked to the example of early-1990s Singapore. Residents in Singapore initially preferred ground-floor apartments for their ease of access, but once elevators became more common and reliable, they came to prefer the higher floors, which offered better ventilation, greater privacy, more picturesque views, and greater distance from the smells of ground-floor trash bins. As buildings in Singapore grew from around ten stories to 20 to 40 stories tall starting in the 1970s, developers adopted T- and Y-shaped floor plans to provide structural stability and space for additional elevators. These basic plan types would be used by architects in China as well.
With the government’s decision in the 1980s to allow features of capitalism into the Chinese economy came the rapid urbanization that continues to this day. Between 1980 and 2020, the Chinese population grew by 500 million. The percentage of people living in cities rose from less than one fifth in the mid-1980s – comparable to England in the early 1700s or the US in 1860 – to two thirds today, on the order of England in the Victorian era or the US in the 1960s. In parallel, there was pent-up demand for housing from existing urban residents. The state-owned industries responsible for constructing danwei housing had underbuilt, since housing construction used up materials and money but didn’t directly contribute to meeting production targets in the way new factories would.
While high-rise developments were originally born out of the impetus to preserve farmland, a 1994 tax reform that shifted 40 percent of local taxes to the central government created incentives for local governments to build on farmland. In China, all land is government-owned, and after the 1994 reform local governments get most of their budget from selling long-term leases – 70 years for housing – to developers rather than from property taxes. This meant that cities had to keep growing in order to balance their budgets. In the 2000s, selling land leases made up 30 to 70 percent of local governments’ annual revenue.
This practice is at odds with the central government’s policy of preserving farms. But the government tolerates it in service of maximizing economic growth. High-rise real estate development excels at creating large demand for concrete, steel, and other industries. Add to that the large quantity of housing needed for China’s rapidly growing population, and sacrificing some farmland to high-density development became more palatable. Today, China builds both up and out.
Indirect effects: nail houses and urban villages
In addition to building on farmland, local governments redevelop existing neighborhoods into microdistricts. However, redevelopment is both more expensive and more time consuming than building on undeveloped land because existing residents had to be compensated (after previous economic reforms gave them ownership of their homes and the right to use the land it sat on). For example, the cost to compensate existing residents of an urban Chongqing neighborhood was about 25 percent of the eventual sale price of the land lease.
The fast pace of development has also meant that cities have sometimes sold land leases to developers before buying out all of the existing residents. Sometimes, construction started before the site acquisition was even complete, leading to the infamous ‘nail houses’ – homes owned by residents who refuse to vacate them – in the middle of construction sites.
As xiaoqu developments began to sprawl outwards onto farmland, starting with Shenzhen in the 1980s, they wrapped around existing farming villages. These villages subsequently urbanized in a singular way, becoming densely packed urban villages known as 城中村, or ‘village in the middle of the city’. This is not a uniquely Chinese practice – many cities, including nineteenth-century Paris and twentieth-century Tokyo, developed this way.
The most famous examples of these are in Shenzhen, which was given special economic zone status in 1980 and had a head start in urban development. To avoid the messy problems of evictions, relocations, and nail houses, governments would redevelop the surrounding fields but not the village itself. So, unlike planned xiaoqu neighborhoods, urban villages were redeveloped informally. With farmland paved over, villagers began to replace their former homes with multistory buildings, renting out the additional units and making a living as landlords instead of farmers. They rented to migrant workers from more remote villages who could not afford a home in the city or who were not legally allowed to buy or rent regular housing in the city due to China’s hukou (household registration) system.
Buildings in urban villages are usually constructed without permits and don’t follow the national code’s sunlight requirement; they’re often called ‘handshake buildings’ because residents can reach out the window and shake hands with their neighbors. Urban villages in large cities can have floor area ratios of 8.0 and higher, much denser than the code-compliant xiaoqu towers, which have a floor-area ratio closer to 2.0 than to 4.0 once internal roads are factored in. This makes redevelopment challenging since compensating residents in the form of a new apartment on the same site is not possible. As a result, many urban villages remain, even though the general policy is to demolish and rebuild them into xiaoqus.
Forms determine form
In China, ongoing urbanization and rising incomes will continue to add to housing demand even as the total population declines, as the nation’s urbanization rate grows towards the 80 to 90 percent typical of developed countries. In the US, cities continue to densify, especially near jobs, colleges, and transit stations. In both countries, housing demand and home prices will remain elevated in the largest cities with the highest-paying jobs.
But while urban areas in both countries continue to build up, they do so without converging in style. In the 2000s, when tower developments became popular, Chinese developers would market their housing as ‘like living abroad’, giving them US- and European-inspired names and designs. The truth is that these buildings are unique to the People’s Republic. The urban villages of the 2000s and suburban tower developments of the 2010s do not have a Western counterpart in form other than public housing projects built in the decades immediately after World War II. We might have thought of such a divergence as cultural in nature. But the urban form in Taiwan is completely different – as is to some extent that in Hong Kong – although they share much of the same cultural heritage.
Whether xiaoqu, 5-over-1, or urban villages, with near certainty we can predict what new Chinese and American neighborhoods will look like by extrapolating from two publicly available documents that 99 percent of their residents have never heard of: the US International Building Code and the Chinese national code.
This should make us more optimistic about the ability of vigorous reformers to change and improve cities. Modern urban form is not always, and perhaps not even usually, an emanation of deep cultural preferences. Changing it does not necessarily mean changing the hearts of millions of people. To build very differently would not take overthrowing twenty centuries of urban culture. It would merely mean tweaking these obscure and somewhat arbitrary documents.