Typology: Adaptive Re-use 2
Challenges that look at repurposing existing architecture by re-inventing it's functions
Challenges that look at repurposing existing architecture by re-inventing it's functions
This is the UNI editorial home for adaptive reuse architecture — the practice of transforming existing buildings into new uses rather than demolishing and rebuilding. It is the most important architectural discipline of the 2020s, for a simple reason: the carbon is already there. Every existing building represents decades of embodied carbon, millions of tons of material, and generations of human memory. Tearing it down and starting over throws all of that away. Transforming it — adapting, renovating, repurposing, adding — keeps the investment alive and responds to the climate emergency with the single most powerful tool architecture has: not building new.
This section curates UNI competitions focused on adaptive reuse across every typology: office-to-residential conversions, industrial-to-cultural transformations (Tate Modern, Fiat Lingotto, CaixaForum), church-to-residential conversions, military-to-civilian repurposing, retail extinction and dead mall redevelopment, and the full spectrum of existing-building transformation. For the heritage-focused dimension, see our complementary heritage conservation and adaptive reuse section.
Adaptive reuse is the practice of changing a building's function while preserving its physical structure. It is distinct from renovation (updating a building for the same use), preservation (protecting a building for historical value), and demolition-and-rebuild. The defining move is re-programming: taking a building designed for one purpose and asking what it could become.
A working typology of adaptive reuse approaches:
The construction sector accounts for roughly 40% of global CO2 emissions. Approximately half of that is operational (heating, cooling, lighting), and the other half is embodied carbon — the emissions locked into the materials, manufacturing, and construction of a building itself. Demolishing an existing building and building a new one in its place releases the embodied carbon of the original construction (through waste) and generates new embodied carbon (through fresh construction). Adaptive reuse cuts that loop almost entirely. The greenest building is the one already standing.
Beyond the background climate argument, the foreground events of 2024-2026 have made adaptive reuse urgent on commercial, policy, and housing grounds simultaneously:
This is the manifesto line of Lacaton & Vassal, the French architectural practice awarded the Pritzker Prize in 2021. Anne Lacaton and Jean-Philippe Vassal wrote the phrase (with Frédéric Druot) in 2004 in the book PLUS: Les Grands Ensembles de Logements, and they spent the following 20 years building the evidence for it. Their best-known project — the transformation of 530 dwellings in the Grand Parc social housing estate in Bordeaux (with Druot and Christophe Hutin, 2017) — took three existing mid-century concrete tower blocks slated for demolition and instead wrapped them in new winter-garden facades that doubled the livable area of every apartment without displacing residents for more than a few hours per day. The project won the 2019 Mies van der Rohe Award and remains the canonical example of adaptive reuse as social justice.
The Lacaton & Vassal Pritzker win marked the moment when "never demolish" shifted from fringe manifesto to establishment consensus. The architectural profession's most prestigious prize was awarded specifically for not tearing things down.
The defining conversion wave of the 2020s. Post-pandemic office vacancies made commercial buildings in downtown cores economically unviable. Housing crises in the same cities made residential conversions financially attractive. The result: an unprecedented wave of office-to-residential conversion projects, concentrated in New York City, Washington DC, Chicago, Los Angeles, Denver, Philadelphia, San Francisco, and increasingly European cities. The design challenges are real — deep floor plates, central cores, insufficient plumbing stacks, commercial window patterns — but the economics are finally aligned.
The most architecturally celebrated adaptive reuse category. Tate Modern (Herzog & de Meuron, London 2000, expanded 2016) — a former power station transformed into one of the world's most visited art museums — is the canonical contemporary example. Other references: Fiat Lingotto (Renzo Piano, Turin, former car factory), CaixaForum Madrid (Herzog & de Meuron, former power station), Punta della Dogana (Tadao Ando, Venice, former customs house), Garage Museum Moscow (OMA, former bus depot), Zollverein Essen (former coal mine complex, Germany). Industrial buildings often have the structural capacity, ceiling heights, and open floor plates that make them ideal for conversion to museums, performance venues, maker spaces, and mixed-use cultural destinations.
As religious attendance has declined across Europe and parts of North America, former churches, chapels, and monasteries have become available for conversion. Subtypes include church-to-residential (apartments, single-family homes, condos), church-to-cultural (community centres, bookshops, libraries, music venues), and church-to-hospitality (boutique hotels in former monasteries). The design challenge is the disproportion between nave and program — churches were built for vast shared worship, which maps awkwardly onto residential scale.
Decommissioned military installations are among the largest reuse opportunities worldwide. Former barracks become housing, bunkers become art galleries or wine cellars, bases become university campuses or cultural districts. Berlin's Tempelhof Airport (not strictly military but a comparable scale of infrastructure) is a notable European example.
The collapse of mid-tier American retail has left thousands of abandoned shopping malls and department stores. Some are being demolished; others are being converted to housing, medical offices, film studios, schools, and mixed-use developments. The dead mall redevelopment genre is one of the most actively discussed in US architectural and urban planning circles as of 2026.
Some of the most architecturally celebrated adaptive reuse projects involve the most unlikely source buildings. Zeitz MOCAA (Heatherwick Studio, Cape Town 2017) converted a disused grain silo into one of Africa's largest contemporary art museums. Silodam (MVRDV, Amsterdam 2003) converted a grain silo into mixed-use housing. Water towers across Europe and North America have been converted to single-family homes, boutique hotels, and artist studios. Prisons have become hotels (Liberty Hotel, Boston). Hospitals have become housing. Train stations have become markets.
The High Line (James Corner Field Operations + Diller Scofidio + Renfro, NYC 2009-2014) transformed an abandoned elevated rail line into one of the most famous urban parks in the world, launching a global wave of elevated park and linear infrastructure conversions.
The most commercially and socially consequential adaptive reuse conversation in 2026 is the office-to-residential wave. The numbers:
Why office buildings don't convert easily — the design problem:
Despite these challenges, conversion is now often cheaper and faster than new construction. Architects who can solve these problems well have more work than they can handle.
The competitions currently curated in the adaptive re-use section:
For more adaptive reuse briefs across the platform, browse all ongoing competitions.
Adaptive reuse is harder than it looks. The challenges that separate amateur from experienced reuse architects:
Adaptive reuse is the practice of transforming an existing building to serve a new function while preserving its physical structure. It is distinct from renovation (updating a building for the same use), preservation (protecting a building for historical value), and demolition-and-rebuild. Examples include converting a factory into apartments, a church into a cultural centre, or an office tower into residential units.
Historic preservation focuses on protecting a building's physical and cultural heritage — the goal is to keep the building as close to its historic form as possible. Adaptive reuse focuses on giving a building a new functional life — the goal is to keep the structure in productive use, even if that means significant changes to the interior, circulation, or program. The two often overlap in practice.
Often, yes — especially in dense urban cores where land costs are high and new construction is slow. Office-to-residential conversions in Manhattan, Washington DC, and Chicago are currently being delivered at lower cost per unit than comparable new construction. However, adaptive reuse can be more expensive when the existing building has significant hidden conditions (contamination, structural failures) or when heritage protections impose expensive compliance requirements.
Industrial buildings (factories, warehouses, power stations, grain silos) are often the most successful because they have robust structures, generous ceiling heights, and open floor plates. Offices are viable but challenging due to deep floor plates, central cores, and limited plumbing. Churches can convert well but face disproportion challenges. The best candidates are buildings with strong structural bones, good natural light access, and flexible floor plans.
Every existing building represents decades of embodied carbon — the emissions from manufacturing the steel, concrete, brick, glass, and wood it contains, plus the emissions from construction itself. Demolishing that building and building a new one in its place throws away the embodied carbon investment and generates fresh emissions. Adaptive reuse keeps the original embodied carbon "invested" and requires only the emissions of the transformation itself. For most buildings, reuse saves 50-75% of total whole-life carbon compared to demolition and rebuild. This is the single most powerful climate argument architects have.
Lacaton & Vassal (Pritzker 2021, "never demolish" manifesto), David Chipperfield (Neues Museum), Herzog & de Meuron (Tate Modern, CaixaForum), Tadao Ando (Punta della Dogana), Wang Shu / Amateur Architecture Studio (Pritzker 2012, urban mining practice), Heatherwick Studio (Zeitz MOCAA), MVRDV (Silodam, Pyramid of Tirana), OMA (Garage Moscow), and Renzo Piano (Fiat Lingotto).
"Never demolish, never remove or replace — always add, transform, and reuse" is the phrase coined by Anne Lacaton, Jean-Philippe Vassal, and Frédéric Druot in 2004. It became the philosophical foundation of Lacaton & Vassal's entire practice and the basis of their 2021 Pritzker Prize citation. The manifesto argues that architects should treat demolition as a last resort rather than a default, and that most existing buildings can be transformed rather than replaced.
Since the COVID-19 pandemic reduced demand for downtown office space, many US and European cities have experienced 15-30% office vacancy rates. Combined with severe housing shortages in the same cities, this has created economic conditions favourable to converting empty office buildings into residential apartments. As of Q1 2026, the US has approximately 90,300 office-to-residential conversion units in the pipeline — a fourfold increase from 2022. New York City, Washington DC, Chicago, Los Angeles, and Denver are leading the wave.
Yes. Adaptive reuse is a particularly accessible competition category for students because it requires careful site research, typological thinking, and creative reuse of existing forms. Many UNI competitions in this section welcome student entries, and a UNI Membership unlocks unlimited access to every brief on the platform.
UNI editors select briefs where transformation of an existing building is central to the design problem. We welcome office-to-residential conversions, industrial-to-cultural transformations, church and religious building conversions, infrastructure reuse, historic building adaptation, and circular construction projects. See our sister sections heritage conservation and adaptive reuse for heritage-focused briefs and residential and housing innovations for the housing dimension.
Start with: Lacaton, Vassal, Druot PLUS: Les Grands Ensembles de Logements (2004); Anne Lacaton and Jean-Philippe Vassal Freedom of Use; David Chipperfield's published monographs on the Neues Museum; Rodolfo Machado's Old Buildings, New Forms; Sally Stone Undoing Buildings: Adaptive Reuse and Cultural Memory; Fred Scott On Altering Architecture; and Liliane Wong Adaptive Reuse: Extending the Lives of Buildings. For the embodied carbon argument, consult the RIBA 2030 Climate Challenge, the Architecture 2030 Challenge, and the ARUP/C40 Cities whole-life carbon reports.
Beyond adaptive reuse, browse all ongoing competitions, see what's trending, preview upcoming launches, or study the past competitions archive. Related sections include heritage conservation and adaptive reuse (heritage-focused briefs), residential and housing innovations (office-to-housing dimension), disaster resilience and climate adaptation (the climate argument), and free architecture competitions. Want unlimited access to every brief on UNI? Explore UNI Membership.