[Re]thinking Porosity

The growing severity of climate issues challenges the traditional binary perception of land as either liveable or uninhabitable. Consequently, more areas now find themselves in an ambiguous zone of questionable liveability. Coastal, ravine, and riverine regions are especially at risk, with rising sea levels and frequent flooding placing them in an uncertain position between habitable and uninhabitable. As the climate crisis renders the territory more inconstant, it becomes urgent to rethink the relationship between architecture and its surroundings. Can we truly conceive sealed, protective living environments that resist any unpredictability?

The conventional attitudes toward climate-responsive construction, especially in the Anthropocene, tend to defensively exclude all environmental forces from building spaces and fill potential perforations existing at the micro material scale. This phenomenon necessitates a re-evaluation of prevailing architectural practises that often view environmental impacts as negative exclusions. The climate crisis seems only to enhance the attentions for thermal-proofing and isolation in the architecture industry [1]. The manifesto of architectural design turns out to be recessionary, simplifying buildings into shelters to prevent heat, noise, moisture, and wind, but meanwhile simultaneously shaping them with ‘spectacular’ forms. This defensive gesture, compared to many other disciplines actively seeking innovative and open interactions with the environment, appears contradictory.

Behind the intricate, delicate, or sometimes ‘fluid’ envelope, this isolative strategy produces a plain and repeatable typology. The structures are designed with standardised criteria, including precisely controlled wall structure and opening ratio [2]. All interactions with sensible uncertainties will be denied or simply neglected by technological interpretation, as science manipulates comfort through their absence [3].

In another, more evitable way, the controlling forces of architecture usually accompany irreversible variations in terrain and hydrological characteristics. However, once the threshold is exceeded, this resistance-based strategy can systematically undermine the nature of reciprocations, leading to more severe environmental catastrophes and displacement issues [4]. Overlooking the potential impact from surrounding contexts can render buildings vulnerable to shifting environmental conditions, which are becoming more unpredictable and intense. “We are, in fact, exposing ourselves to the elements by virtue of these sealed, conditioned spaces,” as Daniel Barber [1] warned.

These issues drive a keen evolution of mindset, urging us to conceive architecture as a porous and penetrative mass that accommodates interactions, inclusive of both human and non-human elements, and adapts or evolves through their impacts. This porosity in architecture is described by the German architect Alban Janson [5] as ‘the manifold integration of hollow spaces with physical mass…which does not limit our spatial latitude with a solid boundary but rather gives us the feeling that we can follow the infiltrating gaze in order to penetrate different forms and depths spatially as well.’ It manifests the notion of porosity as an integration of filled and hollow spaces on a scale encompassing both space and architecture—a zone of interpenetration. The conventional idea of regarding architecture as a solid boundary, one that ‘changes spatial relationships immediately when going in and coming back out’ [6], is therefore challenged.

In this context, this paper interprets porosity as a fundamental architectural language, focusing on a solid, structural sense. It draws attention to the intermediate elements that facilitate interpenetration, allowing elements from different domains to converge, interact, and leave their traces. This phenomenon transforms architecture into a dynamic scenario that revolves around the constellation of broader contexts, rather than solely fixating on individual objects and formations. Instead of seeking standardisation and resisting environmental dictates, architecture actively collaborates with inconstancy, driven by exploring the potential of material changes and the coexistence of external elements.

But can this penetrative, somehow intangible atmospheric character present itself as a concrete space or element, instead of fluctuating in-between? The idea of a porous urban environment was seminally narrated by Benjamin and Lacis [7] in 1925, portraying Naples as a porous city, stating: ‘As porous as this stone is the architecture. Building and action interpenetrate in the courtyards, arcades, and stairways.’ Such permeability between the internal and external gives rise to complex interplays of material and space, concurrently invigorating urban spaces with life. They blur the sharp division by which the external space is located outside the building masses, where the interior is contained within: ‘In this way, compact architectural masses become perforated, dissected, they become increasingly porous.’ [8]. The architectural elements that compose space can be assembled in a loose gesture, instead of always appearing as seamless and compact volumes. Steam, air, and moisture permeate through staggered joints, rafters, and openings, dynamically shaping the spatial depth. The porous structure invites environmental forces to contribute to the atmospheric character of space. The material and quality of architecture, in this process, no longer passively decline while resisting forces but rather collaborate with environmental forces, forming a constellation of spatial situations. This permeable relationship between objects and material, therefore, makes the perception of atmospheric porosity in architecture not ‘merely visual perception or the considerations of form’ [9].

This differentiation can be resonant with Colin Rowe and Robert Slutzky’s investigation on transparency and its division into literal transparency and phenomenal transparency, where the former describes the transparent quality of material referring to a visual experience; yet the latter underlines the perceptual attributes that minds can interact with conceived and indefinite architectural qualities [10]. From the apparent definition, both porosity and transparency seem to deal with the relationship between exterior and interior environments. This ‘binary distinction’, as architectural theorist Detlef Mertins [11] argues, unilaterally indicates the spatial expressions through the human perception level and ‘only touches the surface of phenomenological criteria’ [12]. Therefore, although the theory of transparency has been widely absorbed within architectural culture, it solely establishes an appreciation perspective that explains the permeable quality through human spatial experience, rather than a design method that defines or enriches geometrical depths of elements.

In the context of the above critiques, porosity, defined as a permeable edge between the external and internal realms, deals with the physical quality of architectural elements to foster the ‘spatial extension’ of environmental forces beyond solely human perceptions through a phenomenological lens. It draws attention to the participation of non-human objects in architecture and treats the interaction of objects as a heterogeneous network of non-dominant relations. Philosopher Graham Harman expresses this idea in his Object-Oriented Ontology: ‘the world is clearly not the world as manifest to humans…To think a reality beyond our thinking is not nonsense, but obligatory. [13]’ Porous architecture, which conceives staggers, recessions, and openings in architectural forms, accommodates and collaborates with non-human objects and the accompanying uncertainty from environmental variations. This integration results in an organic structure of space, encompassing the status switching between consistency and temporality; the communication between public and intimacy; the various interactions between envelope and depth; the in-between force of resistance and accommodation. Environment and architecture interplay in tight hollow spaces and small pores while remaining mutually autonomous [14]. These non-dominant relations are an essential prerequisite for constructing an environment in which humans and non-humans can coexist.

This section studies constructed buildings by British architect Peter Salter and Studio Muoto, both of whom have developed their projects with a sensitive association of environments, investigating the tangible implications of porosity in real-world scenarios. The selection of these two cases, namely the Mountain Pavilion by Peter Salter and the Public Condenser at Paris-Saclay University by Muoto, is rooted in the shared characteristic of constructing a porous and interweaving skin system that intimately connects the architectures with their immediate surroundings. Each project interprets the concept of architectural porosity by prioritising environment cognition and human behaviour as primary mediating objectives.

The two aforementioned cases represent responsive buildings that either adapt and accommodate natural forces in changing climate conditions or adjust the building’s climate strategy based on occupancy scenarios. This interplay between architectural spaces and environments is facilitated by the porosity in design. The concept of porous architecture challenges the distinct dividing role of the façade, differing from the purported transparent architecture that merely generates visual perceptions through the building into its surroundings, or mimics nature in forms.

Porosity is suggested as a notion of interiority that envisions a heterogeneous and interweaving relationship between architecture and its situated context. It proposes an objective-oriented design strategy, acting as a permeable intermediary between human and non-human elements. These objects are invited to participate in the creation of space, each showcasing their distinctive roles. This vibrant interplay of interactions and displays emerges in a cyclical dance, harmonizing the acts of consumption and rejuvenation. Muoto [2] describes such architectures as those “ready to admit rain and wind, and perhaps even mould and bacteria, as components just as fundamental as brick and steel.” The structural porosity facilitates the trails of steam, wind, and moisture between the loosely assembled structures, ultimately permeating the surrounding environments. The interface between void and mass is no longer divisions with standardised openings but rather layered and staggered space, a zone of interpenetration [18].

Viewing the idea of porosity in architecture through Graham Harman’s Object-Oriented Ontology, we realize that architecture can serve as a medium between human and non-human participants, even the minor and intangible ones. Considering architectural strategy in relation to surrounding environments beyond human perception allows us to assess the building’s inherent quality to respond to variations.

This exploration of architectural porosity not only serves as a theoretical framework but also offers a compelling vision for architecture that adeptly navigates rapid changes. The significance of a porous architectural language is significantly underestimated in current practice, one that not only reflects but also embraces natural forces, illustrating an interactive dialogue between the built environment and its surroundings. Porosity emerges as a subtle yet potent mediator, facilitating a dynamic interplay between environmental shifts, biodiversity, and human habitation. This underscores its potential as a transformative architectural design method in the face of uncertainty, prompting important conversations about more inclusive approaches that invite non-human agencies into the realms of architectural design and research methods.