It may sound radical for architects to advocate for not constructing new buildings, but architectural designer Xiefangzheng Sun argues for exactly that. With economic pressures persisting and the environmental toll of new construction under scrutiny, architects are increasingly reevaluating whether building from the ground up remains the most viable path. Across the profession, adaptive reuse architecture has emerged as an essential alternative to demolition and new construction.
Xiefangzheng Sun is an architectural designer who has had extensive experience and involvement in major renovation and reuse projects. He has served as a mentor for the Architectural League of New York and received multiple awards for community engagement, including the Gerry and Bob Virgil Ethic of Service Award from Washington University in St. Louis. He holds a Master in Architecture from Rice University.
Sun maintains a keen interest in the renovation and repurposing of existing built fabric, a focus evident in both his professional practice on reuse projects in New York City and his independent research. Unlike strict historic preservation, which prioritizes museum-like restoration to a specific historical period, adaptive reuse focuses on functional transformation, converting aging structures to meet contemporary civic and commercial needs. By preserving structural foundations and framing, building repurposing drastically reduces embodied carbon in buildings and diverts tons of demolition waste from landfills. These existing parameters also supply productive constraints that spur inventive architectural solutions.
Growing up in China, Sun witnessed firsthand the explosive urban expansion and extensive building campaigns across Chinese cities following the economic reforms of the 1980s. He began to form his own critique of contemporary Chinese urban planning through the research project “Fuzzy Collectives,” which categorizes urban development into three core conditions: Bigness, FLABBness, and Fuzziness.
The term “bigness” captures the scale of contemporary Chinese urban planning. According to Sun, Chinese cities experienced two primary waves of development over the past half-century, with the more recent wave generating an omnipresent condition of outsized development. Following the 1978 economic reforms that permitted commercial land development, real estate became a primary revenue driver for municipal governments. Outlying villages and agricultural plots were systematically consolidated and rezoned into massive parcels. To maximize investment returns, these developments produced singular, inward-looking typologies such as isolated office towers, massive retail malls, or gated residential superblocks. Large corporate entities developed these complexes, which are primarily occupied by institutional tenants.
Sun argues that this architecture of bigness fosters an urban language of illegibility. Volumetric forms are typically clad in uniform curtain walls that obscure interior functions, transforming structures into self-contained architectural islands. This insularity dismantles traditional public realms and eliminates the vital interstitial spaces between collective and individual life. As municipal streets lose their civic utility, enclosed commercial developments become the default sites for public gathering, subjecting public life to private surveillance and restrictive operating hours.
In contrast to the scale of bigness, the research highlights an earlier typology: the planned-economy housing blocks constructed over several decades beginning in the 1950s. Centrally planned and built at modest scales, these structures represent an era defined by collective frugality. Sun refers to them as Five-Four-Level-Apartment-Business-Buildings (FLABBs), noting their ubiquity across Chinese cities and their enduring presence in collective memory.
FLABBs represent an urban philosophy distinct from the architecture of bigness. Neighborhoods characterized by FLABBs maintain a human-centered scale defined by narrower streets, porous edges, and compact building footprints. Over time, the ground-level facades of these residential blocks organically converted into active street fronts hosting restaurants, markets, general stores, and medical clinics.
This grassroots commercial growth established dense, vibrant corridors. While occasionally noncompliant with modern codes and spatially constrained, the variety of independent operators fosters local commerce and accessibility. The modest spatial footprints and low operational overhead allow small businesses to provide genuinely affordable everyday services to the surrounding neighborhood.
FLABBs remain legible, accessible, and programmatically adaptable. Commercial activities frequently extend onto sidewalks, activating the streetscape and reinforcing community visibility. The dimensions of these ground-level shops directly correspond to the apartment footprints above. Because the residential units rely on regular concrete shear-wall assemblies, horizontal growth is naturally restricted to distinct structural bays, maintaining human-scale proportions while accommodating phased commercial adaptations.
Sun’s research project investigates how the FLABB typology can be systematically transformed to restore urban vitality and commercial density to city centers. Through targeted interventions that combine selective demolition, light-touch structural additions, and spatial reconfiguration, the proposal activates the latent program neutrality of FLABB structures. At the block level, rigid urban gestalts yield to spatial porosity and layered pedestrian circulation.
This process results in an urban condition Sun terms “fuzziness.” As building layouts become program-neutral, the boundaries dividing living, working, and civic spaces blur, dismantling rigid functional separation across the city block. Strategic cuts, removals, and structural insertions soften the monolithic grain of the original blocks, accommodating the complex interplay between individual privacy and communal engagement.
Given the widespread prevalence of both bigness and FLABB typologies, adaptive reuse strategies of this kind apply to numerous contexts. Sun selected Beijing for the study due to its policy significance and its substantial concentration of large historic housing superblocks. Many of these sites remain as artifacts of the “danwei” system, in which state bureaus and industrial enterprises provided integrated housing for workers. Within Beijing’s Jinsong neighborhood, most apartment blocks share a uniform 16-meter point-loaded module, creating a standardized testing ground for architectural interventions. The study centers on Section 6 of Jinsong, a sector featuring typical neighborhood conditions such as east-west avenues, north-south connectors, alleys, and intersections.
Within “Fuzzy Collectives,” Sun outlines an adaptive framework applied across five existing point-loaded apartment buildings. At the urban scale, targeted architectural interventions break down the monolithic layout of the housing block, introducing layered permeability and communal gathering spaces. At the building scale, structural modifications enhance interior flexibility, enabling units to transition smoothly between residential, cultural, and commercial uses.
Key interventions in the proposal include:
- Conversions of existing apartment blocks into a program-neutral structural framework
- The insertion of a flexible “car collector” structure adaptable to multiple community uses
- Two-story shophouse additions along active street edges
- Adaptation of underutilized accessory buildings for communal functions
- Integrated shared amenities and public courtyards
The “Fuzzy Collectives” framework demonstrates both technical feasibility and urban sensitivity. By prioritizing the adaptive reuse of existing concrete frameworks rather than full demolition, the strategy preserves carbon investments and minimizes community displacement. The model illustrates how aging residential blocks can be upgraded to satisfy contemporary zoning, seismic, and sustainability standards without erasing their urban identity.
Sun continues his work in architectural practice, focusing on designs that advance environmental responsibility and social equity. His ongoing portfolio is accessible at sunxiefangzheng.com.
