Blur Building, Lake Neuchatel, Yverdon-les-Bains, Switzerland, 2002. Image Courtesy of Diller Scofidio + Renfro
Architecture is traditionally chronicled through the persistence of the solid. We define the discipline by the weight of the lintel, the mass of the pier, and the resistance of the wall. Even when lightness is invoked, it is usually understood as a subtractive act, the thinning of a section or the precarious reduction of a load. Yet there is a parallel history, less visible and harder to isolate, in which the primary material of construction is not what occupies space, but what moves through it.
To treat air as a medium is to move past the binary of the envelope. The boundary between the interior and the world ceases to be a line of absolute separation and becomes, instead, a site of filtration and pressure. We begin to see the building as a thermal valve, a series of gradients where moisture, velocity, and heat are not merely background "conditions" to be mitigated by mechanical systems, but are the very substances being shaped.
Establishing thermal comfort once demanded a far more deliberate and calibrated architectural intelligence—an interplay of orientation, massing, material behavior, ventilation potential, shading, and the ways daylight and surfaces absorb and release heat. This was not simply a matter of taste, but of necessity. When many of Hong Kong's post-war modernist buildings were constructed in the late 1960s and 1970s, forming a substantial portion of the city's public housing and broader residential stock, air-conditioning was not yet a ubiquitous, default service. Cooling, where present at all, was limited and unevenly distributed; comfort had to be negotiated through passive means, through section, façade depth, operable openings, and climatic detailing. It was only later, particularly through the 1970s and 1980s, as air-conditioning became increasingly standardized across the region, that mechanical cooling began to displace this earlier matrix of architectural decision-making.
Did air conditioning negatively affect architectural space, particularly in Hong Kong and the nearby region? The more precise claim is that widespread reliance on AC has profoundly rearranged the incentive structure of building design.
In temperate and cold climates, architecture typically begins with a defensive gesture. The building envelope is a sealed boundary designed to resist the exterior environment through insulation, vapor barriers, and mechanical control. In cold countries like Canada, where winter temperatures can plunge well below freezing, airtightness is not a luxury. In this context, buildings must resist the exterior environment entirely to maintain interior comfort. However, in Central America, a region spanning from Belize to Panama, architectural logic shifts from exclusion to negotiation. In this region, the envelope is not a wall of defense but a specialized filter.
Costa Rica is a small country in Central America, internationally renowned for its tourism, biodiversity, and tropical climate. Given this context, tropical design strategies for hotel design are often more studied, but residential cabin projects can represent a more surgical approach to understanding the landscape. Often situated in remote forest or jungle locations, these cabins, apart from the common tropical design strategies, have to prioritize long-term durability and low-maintenance costs, particularly in regions where access for repairs is logistically difficult. This necessitates a design philosophy that favors both structural and climatic resilience.
Building in this context requires precise design responses to two primary environmental stressors: extreme precipitation and high humidity. Costa Rica's tropical climate, while varying by altitude, generally delivers an average monthly rainfall exceeding 150 mm in many regions. This constant water load can create a "wet-bulb" effect, where stagnant, saturated air accelerates interior material degradation and creates physiological discomfort for the inhabitants. To design effectively under these conditions, contemporary cabin architecture employs a three-fold strategy of minimal site invasion, the creation of thermal gradients, and passive climate mitigation.
Much more than merely as a protective skin, the building envelope functions as a thermal regulator that influences operational energy demand, indoor comfort, and long-term efficiency. And before renewable systems or mechanical strategies are introduced, performance begins in section. The way walls, roofs, windows and floors are layered determines how much heat is lost in winter, gained in summer, and ultimately how much energy a building consumes. At the center of this evaluation lies a fundamental metric: the thermal transmittance, or U-value. Understanding how to calculate it is essential for assessing whether an envelope conserves energy or allows it to escape.
Conceptually, thermal transmittance relates heat flow to both surface area and temperature difference. It expresses how much energy crosses one square meter of envelope for each degree of thermal gradient between its two faces.
If we divide 1 m2 of our envelope by the temperature difference between its faces, we will obtain a value that corresponds to the thermal transmittance, also called U-Value. This value tells us a building's level of thermal insulation in relation to the percentage of energy that passes through it; if the resulting number is low we will have a well-isolated surface and, on the contrary, a high number alerts us of a thermally deficient surface.
On a hot afternoon in May, when the air over western India turns metallic with heat, no one remembers façade composition. They remember where the shade falls. They remember which corridor breathed. They remember the house that was cooler than the street. What stays in memory is comfort beyond the form. Repeated thermal preference stabilizes into spatial configuration, and over time, those configurations become building types.
Series 8670 Casement Window. Image Courtesy of Western Window Systems
Windows have long held an ambivalent role in architecture, as they both define and enclose interiors while simultaneously creating a link to the outdoors. This dual function goes beyond simply meeting construction needs or providing daylight, directly influencing how occupants experience and engage with the views. The 20th century saw the introduction of materials such as steel, aluminum, and glass, which enabled different types of windows with thinner frames and expansive panes, enhancing transparency and reinforcing the visual connection with the surrounding setting.
American architects such as Frank Lloyd Wright and Philip Johnson explored these possibilities to harmonize architecture with landscape. In Fallingwater House, windows and terraces seamlessly connect the house to the waterfall and surrounding forest, whereas the Glass House's minimal framing nearly dissolves the boundary between interior and exterior, bringing the natural environment to life inside the house. Through its evolution, windows have become an element that unites space, materials, and perception, opening new pathways for exploring the relationship between architecture and its environment.
https://www.archdaily.com/1034016/framing-interiors-and-landscapes-in-aluminum-and-glass-to-master-the-viewEnrique Tovar
SL500 Sliding Door System. Image Courtesy of ASSA ABLOY
Throughout history, doors—and later automatic doors—have served a far greater purpose than merely marking an entrance or exit. They define thresholds, guide the flow of movement, and subtly shape the way people interact within a space. We can trace their evolution back to the 1st century, when Heron of Alexandria devised a steam-powered door—an early example of technology merging with architecture. Since then, contactless automatic door systems have incorporated technological advancements that enhance operation and redefine their role within buildings. Today, they are integrated across a range of building types and scales, acting as transitional elements that enhance comfort, energy efficiency, and the overall quality of indoor spaces.
https://www.archdaily.com/1029498/the-greener-future-of-automatic-door-systems-a-shift-in-design-and-performanceEnrique Tovar
Aerial view of Beta Building in Honduras. Image Courtesy of Taller ACÁ
Understanding the temperature gradient in a building is essential in cold or temperate climates, where airtight enclosures and continuous insulation are used to prevent heat loss. However, this approach is not suitable for tropical areas like Central America, where the climate is marked by a consistent alternation between wet and dry seasons rather than four distinct ones. Factors such as proximity to the sea, elevation, and local topography influence microclimates across short distances, but high humidity remains a common challenge. Sealed, airtight walls with no ventilation can quickly become breeding grounds for mold, making the thermal strategies of temperate climates problematic. In response, local designers have developed alternative approaches that embrace, rather than resist, the outdoor environment, allowing airflow and evaporation to manage interior comfort.
Polycarbonate, commonly used in roofing and industrial cladding, has gone beyond its initial applications to become a material widely used across various architectural typologies. Its combination of strength, lightness, easy installation, and ability to allow natural light to pass through has made it an attractive option for residential,educational, and even cultural architecture projects. In homes, polycarbonate not only helps create bright and comfortable environments but also allows for creative use of translucency to generate private spaces without sacrificing visual connection to the outdoors.
Vernacular construction technologies are based on centuries of practical wisdom, refined through countless trials and errors. This process eliminates all irrelevant aspects, creating highly efficient and simple systems that are intrinsically adapted to the local climate and resources. These methods demonstrate how to conserve heat with minimal energy, offering valuable insights for modern buildings, promoting energy efficiency, and environmental harmony. In this article, we have already covered traditional passive cooling techniques, such as Persian wind towers and Arab mashrabiya. Now, we turn our focus to strategies applicable to cold climates, exploring effective solutions for heat retention and space heating.
Over-providing traditionally implies offering more than is necessary, often carrying a negative connotation due to the potential for excess and waste. However, could there be scenarios within the built environment where over-providing proves advantageous? The question critically examines how overprovisioning might enhance a building's flexibility and adaptability to diverse and evolving conditions.
The underlying assumption of accurately providing what is needed for a building is that stakeholders—including owners, architects, and designers—can accurately predict and cater to a structure's current and future needs. This assumption, however, is challenging to realize, as societal, economic, and cultural shifts frequently occur in unpredictable ways. In this context, over-providing emerges as a counterintuitive yet potentially beneficial strategy. As buildings and structures inevitably transform, those designed with inherent adaptability reduce the need for costly renovations or complete rebuilds.
Abu Dhabi Climate Resilience Initiative / CBT Architects. Image Courtesy of CBT Architects
As temperatures rise globally, the impacts of urban heat islands—once considered an invisible threat—are becoming increasingly pronounced and ever more dangerous. Despite this mounting threat, however, the public realm which constitutes about 30% of cities offers immense potential to provide respite from scorching heat and introduce new opportunities to improve urban resilience efforts. As global temperatures rise, cities in regions like the United Arab Emirates and India are facing unprecedented challenges in maintaining livable urban spaces.
ICON, the office that pioneered large-scale 3D printing, has announced a new residential development of 3D-printed homes to take shape at Wimberley Springs, in Texas, United States. The complex, comprising 8 single-family homes, features designs from ICON’s CODEX Digital Architecture Catalog. The houses, currently under construction and available for sale, leverage ICON’s robotic technologies to create an energy-efficient, low-carbon construction process.
Thermal mass is the ability of a material to absorb, store, and release heat. Used to moderate building temperatures by reducing fluctuations, the concept is crucial in improving energy efficiency. Materials with relatively high thermal mass, such as stone, concrete, rammed earth, and brick, can absorb significant heat during the day and release it slowly when temperatures drop at night, reducing the need for heating and cooling systems. Properties like heat capacity, thermal conductivity, and density are all considered when assessing the thermal mass property of a material.
A Trombe wall is a passive solar building feature that enhances thermal efficiency. Positioned on the sun-facing side of a structure, it consists of a wall made from materials like brick, stone, or concrete, and a glass panel or polycarbonate sheet placed a few centimeters in front of it. Solar radiation penetrates the glass during daylight hours and heats the masonry wall. This wall then slowly releases the stored heat into the building during the cooler nighttime hours, maintaining a more consistent indoor temperature without the need for active heating systems.
For centuries, arid environments have solved the problem of light, privacy, and heat through a statement architectural feature of Islamic and Arab architecture, the mashrabiya. Crafted from geometric patterns traditionally made from short lengths of turned wood, the mashrabiya features lattice-like patterns that form large areas. Traditionally, it was used to catch wind and offer passive cooling in the dry Middle Eastern desert heat. Frequently used on the side street of a built structure, water jars, and basins were placed inside it to activate evaporative cooling. The cool air from the street would pass through the wooden screen, providing air movement for the occupants.
Similar to the Indian jali, the vernacular language also offers a playful experience with daylight while still maintaining a certain degree of privacy. Traced back to Ottoman origins, the perforated screens protected occupants’ from the sun while simultaneously letting daylight through in calculated doses. Although the mashrabiya was a statement in arab and Islamic architecture languages, it wasn’t until 1987 that the archetypal element began appearing with a revised contemporary application.
