My first, fleeting encounter with the Ökohaus (Eco-House) project came during an all too brief visit to Berlin in November 2017. I had been invited by a close friend from my then-recent graduate studies to join her on the Berlin leg of a far more sprawling research trip, in which she was exploring and documenting exceptional examples of social and affordable housing in Europe. Unsurprisingly, the itinerary for our roughly week-long stint in the city consisted to no small extent of a self-guided walking tour from one Google Maps pin to the next, nearly all transposed directly from a May 1987 special issue of the Japanese magazine A+U dedicated to the, Internationale Bauausstellung 1987 (IBA), or International Building Exhibition, urban renewal program, of which the Ökohaus was merely one of more than one hundred projects.
At first glance, this cluster of three modestly scaled and irregularly oriented residential buildings were perplexing, seemingly marked by a kind of double informality. The dense, overgrown foliage of the surrounding site, which appears to envelop the buildings from readily accessible vantage points, lends it something of the aesthetics of the ruin. The surprising patchwork of cladding materials and fenestration strategies that wrap the structures’ irregular, angled tiers is also faintly evocative of the improvised, ad hoc construction that frequently corresponds to collective occupation and adaptation of abandoned or unfinished structures — a kind of anti-aesthetics. Even a moment of sustained attention to the project, however, suffices to dispel any impression of informality. While the puzzle-like complexity of the buildings couldn’t possibly be untangled in the span of such a brief exploration, it quickly became clear that this complex bricolage of materials — timber siding and paneling of various dimensions and orientations, and variously painted in vivid colors or simply sealed against the elements; wooden and metallic shingles, some organized to produce a polychromy reminiscent of the diagonal stripes of hazard signage; aluminum and galvanized steel flashing; wooden and metallic mullions of different colors and finishes, canted at a variety of angles; glass panels of various tints; exposed in situ concrete; textured stucco; etc. — was resolved with immense precision and care.
When the municipal government of West Berlin launched the initial planning stage the IBA in 1979, vacant sites and even lingering debris from buildings decimated by Allied bombs in the Second World War could still be found on both sides of the divided city1. Much like the earlier Interbau, a like minded revitalization program staged in 1957, which saw most famously to the resuscitation of the Hansaviertel district in the form of a verdant park punctuated by a constellation of low- and mid-rise modernist housing blocks — some designed by such international luminaries as Walter Gropius, Oscar Niemeyer, Alvar Aalto, and Arne Jacobsen — the IBA ‘87 program sought to respond to a persisting crisis of affordable housing and social infrastructure in a West Berlin. In contrast to that earlier initiative, however, the sites it sought to revitalize tended to be smaller for the most part, often comprising infill lots packed tightly into the city’s urban fabric, and most importantly, scattered across four areas of the city. While the southernmost portion of Tiergarten, with its heavily wooded landscape, was originally intended to serve as the exclusive site of the IBA program — echoing, essentially, the basic strategy of the Interbau ‘57 — it was ultimately decided that the project’s resources would be better spent if they could benefit the renewal of three other districts as well: Tegel, Prager Platz, and Southern Friedrichstadt. “Neubau” (translating from German to new, freestanding construction), and “Altbau” (meaning buildings incorporating aspects of, or at least more contingent on the negotiation of, existing structures) were handled by different administrative bodies within the larger umbrella of the IBA organization.
The scope of IBA ‘87 was sprawling. Its participants were no less internationally renowned, and were, in fact, far more diverse, both geographically and culturally, than their postwar forerunners, with leading practitioners from the United States, England, France, Italy, Switzerland, Spain, Portugal, the Netherlands, Austria, and Japan receiving invitations to contribute designs. It is perhaps unsurprising then that the buildings realized as part of IBA ‘87 were also far more stylistically diverse than the constituent projects of the Hansaviertel had been, reflecting a collapse of the apparently international postwar consensus around the efficacy of an industrially-driven and techno-positivistic modern architecture, and the more fragmented architectural discourse that emerged in its wake.
“What at least can be said is that the architecture which goes to make up the IBA is more or less devoid of what has come to be called postmodernism. There are works of Rationalism, Historicism, Structuralism, and even Expressionism, but all seem to have come together into a harmonious whole,” wrote A+U editor Toshio Nakamura in his introduction to the magazine’s special edition. At the time, this assessment must have seemed appropriately nuanced in its refusal to treat these smaller stylistic developments as part of a more monolithic cultural movement. Yet with the benefit of historical distance, this also comes across as perhaps a bit naive. Charles Jencks’s influential book Language of Post-Modern Architecture (1977) — with its notorious declaration of “the death of modern architecture” accompanying images from the televised demolition of Minoru Yamasaki’s Pruitt-Igoe housing complex in the summer of 1972 — had been published just two years prior to the launch of the IBA’s initial planning phase. The postwar promise of unmitigated economic growth and universal access to the benefits of industrial development offered by proponents of modernization theory had been checked, first by the flourishing of environmental consciousness in the 1960s, and then by the global energy crisis of the 1970s. By the end of that decade, the demise of détente had given rise to resurgent anxieties about the possibility of nuclear conflict between the United States and the Soviet Union, fears that surely would have been felt all the more acutely in Berlin, as the microcosm of Cold War geopolitical and cultural tensions that it had become. French sociologist Edgar Morin, writing with Anne-Brigitte Kern, may not have coined the term polycrisis until the early 1990s, but many of the fundamental conditions that informed its conception began to take shape during this tumultuous period. The effects of this upheaval were no less felt in architecture than in other fields of cultural production.
Suffice it to say, architecture may have been in the midst of a moment of stylistic polyphony, but many contributors to IBA ‘87 were deep in the throes of postmodern thought, seemingly enamored with (though only debatably responsive to) Berlin’s urban history and typological specificity, and given to the formally and compositionally playful tendencies endemic to the period. By and large, the IBA commission’s parceling of project sites signals a rejection of modernist principles of urbanism. Instead, both the initiative’s administrators and many contributing architects took up the tenets of what would soon come to be called New Urbanism, a movement driven by the proposition that pre-modern modes of urban organization more readily lent themselves to the human scale (walkability, essentially), community-building, and “place-making.” Many architects thus sought to respond to the spectral contours of the structures that had once occupied their allotted sites or, at the very least, to adopt a strong position with respect to how their buildings presented to the street. No shortage of sensational facades were constructed as a result of this impulse, though more than a few are decidedly of their moment in their propensity for material and ornamental nostalgia, and have arguably aged poorly.
That the Ökohaus was anomalous to the wider trends of the IBA program was surely unmistakable at the time of its construction, and is all the more pronounced today. Of the many projects envisioned for IBA ‘87, the Ökohaus is perhaps alone in arguably echoing the strategy of freely organizing volumes in a verdant site exemplified in the Hansaviertel, yet here there is none of that project’s manicured attitude towards the landscape or assumption of a tabula rasa. On the contrary, a majority of the trees that obscure the buildings from view today were already standing prior to the project’s conception, and their retention was stipulated in the design brief. The project is more convincingly embedded in its site today after decades of further growth, and stands in ever more marked contrast to the its neighbors across the Rauchstraße, where larger, more organizationally conventional and ornamentally postmodern apartment blocks by Aldo Rossi, Hans Hollein, and others conformed to a formally conservative masterplan by Rob Krier, the Luxembourgish architect and paragon of New Urbanism. The Ökohaus dispensed with the totalizing vision of a perfectly resolved object that characterized a majority of entries, and instead sought to establish the basic conditions for a far more energetic, likely messier, yet potentially more fulfilling process and outcome.
As was the case for a majority of the projects realized for the IBA ‘87 program, the Ökohaus was billed, and continues to be remembered, as the work of a singular creator. Yet for most people, the project’s association with the architect-engineer Frei Otto comes as something of a surprise. Both then and now, the invocation of Otto’s name immediately conjures images of the soaring and geometrically innovative leichte flächentragwerke (“lightweight structures”) with which he became virtually synonymous over the course of a more than sixty-year-long career, beginning with the groundbreaking suite of tent-like pavilions at the 1955 Federal Garden Exhibition in Kassel. The most spectacular and recognizable outcomes of this line of experimentation are the German Pavilion at Expo ‘67 in Montreal and the network of steel cable-net and translucent acrylic canopies designed for the stadia of the 1972 Olympic Games in Munich. In fact, his research and built work are far more versatile. For students and aficionados of architecture, his name may also call to mind black-and-white documentary photographs of the experimental “bubble models” produced at the research institute he established at the University of Stuttgart in 1964, which were used before the advent of digital modeling to formally optimize thin-shell and tensile roof structures, or perhaps the groundbreaking timber lattice gridshell of the Mannheim Multihalle of 1974. One of his early projects consisted in the design, alongside architects Günther Günschel and Karl Otto, and builder Peter Stromeyer, of the rapturously received main pavilion for the “City of the Future” exhibition during Interbau ‘57, a sprawling free-span canopy consisting of a Mero-system space frame topped with a thin membrane of polyurethane-coated white cotton fabric. This last project lends a rich narrative dimension to Otto’s inclusion in the IBA ‘87 program, placing him in biographical proximity to the generation of seasoned modernists whose works grace the Hansaviertel, even as the structural lightness, groundbreaking spatiality, and innovative materiality of this and other works situates him more comfortably in the company of fellow mid-century innovators like Felix Candela, Hans Isler, and especially Buckminster Fuller.
Yet even for those familiar with Otto’s historical position and wider oeuvre, the Ökohaus is something of a curiosity. Whereas some might characterize his earlier, more famous works as formalist—if only in the dully literal sense that they resulted from a novel approach to the generation of architectural form (that is, the calculation of minimal surface)—the Ökohaus can be interpreted as the product of a quite different sort of formal experimentation, one in which the resulting architectural objects were relegated to a secondary tier of concerns in order to foreground the process that shaped them. That is, they were the fruits of a critical attempt to transform the normative protocols of architectural design and building construction, both by prioritizing environmental thinking and by inviting, or insisting upon, the participation of the buildings’ future inhabitants. In contrast to the cultural nostalgia that tinged so many other projects of the IBA ‘87 program, the Ökohaus may therefore be interpreted as yet another expression of Otto’s fundamental (though by no means dogmatically modernist) optimism in regards to the utopian potential of technology, even as it indicates his ever-evolving position with respect to the limits of top-down planning, the urgency of ecological thinking, and the necessity of a more democratic and pluralistic politics.
This brings us back to the question of authorship. However unexpected the attribution of the Ökohaus to Frei Otto may be, and however remote it may seem from his ostensibly typical mode, the fact that he is frequently given sole credit for the project is all too typical of the cultural sector’s habit of elevating individual creators to heroic status. It cannot be overstated, however, that this tendency to heroicize was always fundamentally at odds with Otto’s own career-spanning preference to celebrate the contributions of his myriad collaborators, and his insistence on presenting the remarkable structures upon which his reputation hinged as the products of diverse and dedicated teams comprising specialists from many different fields of knowledge. While such nuance ought to be the norm, this stance can be construed as speaking to Otto’s relative humility or, at any rate, to a stubborn lucidity with respect to the complexities of his field. By the time of the IBA initiative, in fact, Otto had reorganized his practice, Atelier Warmbronn, in such a way that he became almost exclusively involved in projects as a kind of specialized structural and environmental consultant rather than the lead architect. Although the question of authorship warrants critical assessment and additional nuance even in the case of his best known structures, the fact remains that the Ökohaus stands apart from the rest of Otto’s work. Indeed, even acknowledgement of his most immediate partner in the endeavor, the architect Hermann Kendel, would be to miss the forest for the trees.
This is, as the ecstatic incongruity of the building facades insinuates, due to the fact that the various maisonette-style units were developed in accordance with the needs and desires of different occupants, designed by different architects, and built, with a handful of exceptions, by different contractors. Except, of course, in those instances wherein the inhabitants were the designers, the builders, or both. The aim was that each residence would be constructed within one of three reinforced concrete “infrastructures” designed by Otto and Kendel, and erected in a preliminary phase. Each of these structures consisted of four floors of staggered slabs at regular heights of six and twelve meters, which sat atop concrete columns, offset in order to liberate the building perimeter and integrated with electrical, plumbing, and climatic systems that would be shared by all residents. Otto and Kendel conceived of the project such that they would not dictate the design of the units themselves, but rather to serve, only when needed, as advisors to the assorted residents, helping to nurture enthusiasm for the central environmental conceit of the project, and to assist in, though never dictate, the conceptualization of details and methods by which to resolve disparate design ideas (to the extent that this was necessary to ensure the buildings’ functioning). When required, they served to nurture a sense of shared responsibility and communal vision, or to mediate in the almost inevitable instance of friction between inhabitants. Whenever possible, however, they stood out of the way and allowed this micro-political experiment to unfold. As to the residents themselves, newspaper articles and billboards on the construction site were deployed to drum up interest from potential applicants, more than a few of whom retreated in haste upon realizing the likelihood of spiraling costs and unpredictable timetables for the realization of the work. The eighteen individuals who remained engaged were profoundly committed to the project.
The dearth of drawings of the Ökohaus in publications from the period is notable. It stands in stark contrast to the PoMo predilection for ambitious perspectival renderings or Beaux Arts-indebted elevational studies, and speaks to the impossibility of imagining the final product — or rather, to Otto and Kendel’s self-conscious refusal to do so, for fear of influencing the result in contrast to the spirit of the project. Instead, there are a handful of photographs documenting a series of process-oriented models, depicting either the austere concrete structures before the tenants’ arrival, or more often, a rather messy study model notable mostly for an excess of faux vegetation which signals the architects’ aspiration for a sequence of terrace gardens flowing seamlessly into the surrounding forest condition. Many of the images associated with the development of the Ökohaus depict Otto and Kendel gathered around a model of the site as the inhabitants and their respective architects insert 1:50 scale models, one by one, into the model of the three infrastructural frames. These images capture the originating moments of a dynamic community, the constituents of which became collaborators long before they could be described as neighbors, united by a shared commitment to the project in spite of (or perhaps because of) the financial and temporal uncertainty that accompanied it, and to a vision in which, far from being Frei Otto’s domain alone, their share was growing day by day. That is to say, there were Ökohäusler before there was an Ökohaus.
In short, the conception of the Ökohaus is a product of two currents of architectural thought that had been bubbling for decades. One of these, as the project name suggests, is the growing critical emphasis on environmental considerations. A growing consciousness of the adverse effects of industrialization and the unmitigated spread of human settlements began to take root in the sixties and was enriched by the emergence of climate science by the time of the IBA’s early planning stages.2 Otto was considered to be a thought leader in environmentally conscious design, owing both to the lightness, temporality, and material economy of his best known projects, and to his leadership of the Institute for Lightweight Structures in Stuttgart, which had produced rigorously researched publications on everything from inflatable structures to “natural architecture” (that is, constructions by animals, plants, and fungi).
The Ökohaus also embodied another line of thinking known broadly as participatory design. Otto appears to have considered the possibility of such a patchwork building as early as 1951, when he proposed a twelve-unit apartment building as one of his final student projects at TU Berlin3. While the success of Otto’s lightweight structures carried his career in a different direction by the end of that decade, his ideas about housing continued to evolve. He came to emphatically reject a top-down, urban-planning oriented notion of modernist housing, a position informed by the apparently deflating experience of designing and realizing, alongside Leopold Kuhlmann and others, an expansive social housing complex at Berlin-Tempelhof for the developers of the Alexandra Stiftung between 1953 and 1956. This aversion to the model of social housing that was advanced at the Interbau ‘57, and renewed conviction in the promise of the vision he articulated in his earlier student work, is evidenced by a lesser-known proposal for a series of high rise residential structures near New York’s Central Park, which anticipate the aesthetics of the later Ökohaus to a surprising degree.4 By that time, Otto had come into contact with the likes of the French architect and theorist Yona Friedman, who he points to as a key influence in the development of the thinking behind the Ökohaus.
By the time he received IBA Neubau commissioner Josef Paul Kleihues’s 1980 invitation to propose a series of ecologically sensitive residential buildings, it is likely that he was also well-versed in the works of other forward thinking actors whose legacies have been the subject of a critical resuscitation in recent years. One of these is Dutch architect and theorist Nicolaas John Habraken, whose 1962 book Supports: An Alternative to Mass Housing remains a foundational text for proponents of participatory design even today, advocating for architects to focus on the design of the most basic conditions for housing, as well as systems of elements that empower occupants to configure (and reconfigure) their homes to meet evolving needs. Positioned as a riposte to the totalizing modernist visions of housing being built the world over, Habraken’s book may well have enriched Otto’s earlier thinking on the housing question. The Belgian architects Simone and Lucien Kroll also come to mind. Their experimental housing designs began to garner attention in the sixties, and culminated in the the participatory (or incrementalist, in their parlance) design, construction, and subsequent adaptation of the La Mémé, a housing block for the medical school of the Catholic University of Louvain completed in 1970. Contradictory as it may seem, that project’s larger scale and far more complex collection of stakeholders limited the range of strategies available to occupants, resulting in an architectural object of more constrained expression than the more modest Ökohaus. Still, it seems likely that Otto would have been aware, to some degree, of the very public business of La Mémé’s construction by the time of the IBA commission.
The Ökohaus is increasingly recognized by architectural aficionados and casual observers alike as a singular achievement in the history of both participatory design and twentieth century housing more broadly. It has attracted the interest of such contemporary leaders in the realm of adaptive reuse as Arno Brandlhuber (who now occupies the maisonette developed by original inhabitant, architect Manfred Ruprecht), Anne Lacaton, and Jean-Philippe Vassal. In 2012, the project was the subject of the exceptionally detailed documentary Dreaming of a Tree House by Beate Lendt. The Ökohaus received glowing editorial treatment by the likes of T: The NYTimes Style Magazine in 2020 — no doubt owing at least partially to Otto’s lingering reputation as one of the more visionary architects of the last century (so much so that he remains, to date, the only Pritzker Prize winner to receive the award posthumously, in 2015).5 Likewise, his reputation at the time of the project’s conception almost certainly invited the participation of architecturally-inclined residents, yet in the end it bears emphasizing that it is their commitment to and elaboration upon Otto and Kendel’s project that sets the Ökohaus apart. It is likely that the project’s success may be attributed in some measure to its relatively humble scale, and to the sensitivity with which it has been integrated with the flora of the surrounding site, a fact which owes as much to the enthusiastic efforts of autodidact botanists within the project’s community of occupants as to anything Otto and Kendel could have planned. Likewise, many of the architectural details that have permitted its original inhabitants to continue living there for many decades, including the partial glazing of the exterior staircases, were developed by the inhabitants, in some cases over the protestations of Otto himself.6
The more interesting question, then, is whether a model of communal building and communal living that is so provocative, so nuanced, so laden with frictions and rewards alike as the Ökohaus has proved to be, could ever have come into being had it not been so hard won, so contingent on cutting through the totalizing vision of any single author. Early in Lendt’s documentary, while ruminating on the ideas and influences that propelled his work in the 1950s, Otto offers a provocation that may surprise those who assume his work to be formally motivated: “What are the leading ideas for an architecture that distances itself from form? (…) What might a city look like if not prevented from being reasonable by its material and/or its planning?” Later in the film, reflecting on the key lessons of the IBA ‘87 experience, he offers a further meditation on the folly of formalism, in its narrowest and most obvious sense: “Any predefinition of form is basically wrong. Architecture often claims power through form — but how can we build things in such a way that this is avoided? How can we instead accept the forms that unavoidably result [from the process]? These are the basic ideas that have led to the Ökohaus.”7
Finally, it is evident that Otto felt that the genuine achievement of the Ökohaus resides in its prioritization of technique over content — one of several definitions of formalism, as it happens. More precisely, it emphasized processual form over physical form, challenging the prevailing strictures of design and construction, whether dictated by law or by tradition, and accentuating the messy, generative conversation that resulted from the architects’ relinquishing so great a degree of design agency to those who would ultimately call these buildings home. Would such an experiment have taken place — could it have been imagined, let alone brought to fruition — in a milieu of consensus, in the midst of times deemed to be more stable? Here we come again to the matter of the relation of form to crisis. It is a thought worth considering whether the seeming Gordian knot of material and philosophical crises that shook the imaginations of politicians, planners, architects, and indeed city-dwellers from all walks of life in the tumultuous years leading up to the IBA ‘87 program didn’t also constitute the essential conditions, not least the negotiations of egos, required for the conceptualization and realization of this remarkable place and community.
