At Jalmanjar Farmhouse outside Ahmedabad, cooling begins with a perforated facade of compressed earth blocks. This outer skin filters the sun while windcatchers draw air through the enclosure. Behind it, verandas and balconies occupy the shaded space between the outer jali and the inner rooms, and an open courtyard cuts through the center of the plan. The house does have active systems, but much of its thermal work has already started in the wall and in the void before a machine enters the equation.
Before cooling became an appliance, it was an integrated part of the building. Openings faced prevailing winds because air needed a route through the house, and courtyards created cooler pockets close to occupied rooms. Thick masonry slowed the passage of heat, and deep overhangs shaded from solar gain in the first place.
Mechanical air conditioning loosened architects’ reliance on these passive methods. Once a compressor could correct the temperature indoors, architecture gained far more freedom to ignore what the sun and nighttime air were doing outside. Of course, summers are getting hotter and demand for electricity is growing. Designers are revisiting how much of that work the house can take back, and how architecture can regain responsibility for temperature.
Jalmanjar Farmhouse, PYHT — BioArchitects, Ahmedabad, India, 2025 | image © Amalgamate
WHEN THE THERMOSTAT GOES DARK
During power outages, the idea feels much more urgent. It’s during these events that the envelope and the plan determine how quickly heat enters, where it accumulates, and whether cooler air can move through after sunset. Researchers describe this capacity as passive survivability: the ability of a building to maintain tolerable indoor conditions when the systems it normally depends on stop operating.
A 2022 Applied Energy study modeled apartments during the Pacific Northwest heat wave of June 2021 and found that integrated shading and natural ventilation could have lowered peak indoor temperatures in Portland by about 14°C (25 °F) during the three-day event. The same strategies reduced active cooling loads by as much as 80 percent.
With this in mind, a deep overhang or operable window becomes more valuable. It can reduce energy use on an ordinary afternoon, or even become part of the house’s emergency behavior when electricity disappears. The 2022 study focused on a dry-summer climate where cooler nighttime air can be harnessed effectively, which already suggests one of the limits of passive cooling.
A 2026 review mapping 197 residential studies makes the same point at a much larger scale: envelope design, ventilation, shading, and thermal storage work in climate-specific combinations. Their effectiveness changes with building type, local conditions, and how residents operate the house. Of course, there’s no single passive strategy which can be just copied from one climate to another.
Jalmanjar Farmhouse, PYHT — BioArchitects, Ahmedabad, India, 2025 | image © Amalgamate
SHADE CREATES A new ROOM
At Nedarag Guesthouse in southeastern Iran, NextOffice places three residential units beneath a broad palm canopy that floats over a shared courtyard. The roof takes the force of the sun while the dry-stacked stone rooms sit beneath it, separated from the hottest surface by a layer of moving air.
The courtyard becomes part of the cooling system, yet its environmental role is inseparable from how people use it. Guests pass through it and children play there, while local gatherings occupy the same shaded space. Cooling extends beyond the sealed room and starts producing territory where habitation can move outside.
Jalmanjar works through a similar thickness at the edge of the house. PYHT — BioArchitects uses the compressed-earth jali as a porous outer boundary that shades the enclosure and allows air to enter through integrated windcatchers.
The zone behind the screen holds verandas and planted pockets alongside circulation, giving residents a sequence of thermal conditions instead of a hard line between interior and exterior. The payoff is both spatial and environmental, as shade becomes a place to sit and airflow creates a reason for a passage to stay open. A climatic buffer becomes part of the home.
Nedarag Guesthouse, NextOffice, Baluchestan, Iran, 2026 | image © Ehsan Hajirasouliha
THE WALL BUYS TIME
In Jaipur, Malik Architecture turns black sandstone into its House of Solid Stone. Hollow interlocking walls create a thermal break while reducing the amount of stone used, and narrow courtyards slice into the heavy mass to pull light and air deep into the plan. Glazed areas sit behind deep overhangs and hand-cut operable screens. The house makes heat feel physical. Simply put, there is an enormous amount of material between the afternoon sun and the spaces where people sleep and gather.
Thermal mass changes the timing of heat instead of making it disappear. A thick wall absorbs energy and slows its journey toward the room, creating a delay between the hottest part of the day and the moment that heat reaches the interior face.
Meanwhile, at Karm Architecture Lab’s Breathing House in Marsa Alam, where summer temperatures can approach 50°C, fossilized coral-limestone walls reach 45 to 60 centimeters thick. A secondary skin shades the southern elevation, while the plan opens toward prevailing winds from the Red Sea. The wall buys time, meaning that when nighttime temperatures fall enough, accumulated heat can move back out before the next day begins.
Breathing House, Karm Architecture Lab, Marsa Alam, Egypt, 2023 | image © Farah Faheem
HANOI NEEDS A DIFFERENT HOUSE
Bat Trang House in Hanoi breaks the visual pattern of heavy desert masonry with a porous ceramic envelope. VTN Architects wraps the family home in locally made bricks whose openings filter direct sun and let air pass through. Green spaces occupy the layer behind the facade, followed by the inner enclosure, creating a three-part ventilation system through a dense urban house.
The architects say the arrangement removes the need for artificial air conditioning. Its logic belongs to a hot-humid climate, where the dramatic day-to-night temperature swing available to many desert buildings is far smaller and permeability takes on greater importance.
Vo Trong Nghia learned that relationship with climate long before founding VTN Architects. Speaking with designboom in 2021, he recalled growing up in a Vietnamese village without electricity, air conditioning, or even an electric fan: ‘trees, water, ventilation, and sunlight became the most important issues in our lives.‘
His description of cooling was equally direct, with shade from a large tree and wind moving across a pond before entering the home. The sequence is simple, but it points toward a broader principle. Climate-responsive architecture starts with the conditions already present on the site and decides what the house can do with them.
Bat Trang House, Vo Trong Nghia, Hanoi, Vietnam, 2021 | image © Hiroyuki Oki
WHEN HEAT STARTS DRAWING THE PLAN
In Ahilyanagar, Kaushal Tatiya Architects organizes its 7,000-square-foot Anthill House as interconnected brick chambers, borrowing the thermal logic of insect mounds without turning the building into a literal imitation. Courtyards bring air into the plan, while perforated brick walls and ventilation shafts create stack-driven airflow.
A water cascade cools the central living area through evaporation. The need to move heat upward starts shaping the section, while the route of air through the building begins influencing where voids and openings appear.
Kaushal Tatiya Architects, Anthill House, Ahilyanagar, India, 2026 | image © Avesh Gaur
monolithic walls enclose a tall atrium
Casa 1736 brings that same idea into the compressed fabric of Barcelona. HARQUITECTES faced a deep urban lot where the center could easily have become dark and poorly ventilated, so the architects emptied it out. A tall atrium now rises through the house, drawing light downward and encouraging warm air to escape through a roof opening. Thick low-cement monolithic walls add thermal inertia around it.
The environmental device is also the social center of the home, with family spaces gathering around the void. Here, the demand for ventilation helps decide where the household meets.
Casa 1736, HARQUITECTES, Barcelona, Spain, 2024 | image © Adrià Goula
A HOUSE THAT USES THE WHOLE DAY
Zyme Studios considers the sharp temperature changes of California‘s Yucca Valley desert over a full 24-hour cycle with its proposed Oscillation House. Heavy walls store thermal energy, broad overhangs hold direct sun away from the glazing, and an east-side pool cools air through evaporation before operable openings draw it across the interior. Each move contributes a little. Together they reduce the amount of heat the mechanical system eventually has to remove.
A house organized around these exchanges asks for a different relationship with comfort. The afternoon and the night are allowed to behave differently. A shaded exterior room may become useful when the sun shifts. Openings gain value after temperatures fall, while thermal mass releases energy accumulated hours earlier.
The building is working across time, and the resident begins reading it that way. The thermostat’s promise of one stable indoor temperature is replaced by a home whose cooler and warmer zones move through the day.
Oscillation House, Zyme Studios, California, USA, 2023 | image courtesy Zyme Studios
PASSIVE SURVIVABILITY ENTERS THE FLOOR PLAN
Recent research is beginning to put numbers around how much the geometry of a home can change its performance in extreme heat. A 2026 Energy and Buildings study analyzed 6,931 real apartment plans and grouped them into 36 representative types before simulating them across 20 historic heat waves in a hot-humid climate.
Every archetype crossed the study’s thermal-safety threshold within 36 hours during the modeled outage conditions, with survivability pressure rising sharply around 20 to 22 hours. Smaller units experienced greater peak heat stress, while differences in spatial configuration affected how overheating developed within the apartments.
Austin’s City Park Residence brings that concern into a contemporary American house. Alterstudio uses breezeways and deep eaves to reduce heat gain and encourage passive cooling, while the wider design responds explicitly to Texas power-grid instability and extreme weather.
The project shifts the conversation from efficiency toward resilience. An efficient house may consume relatively little energy while all of its systems are available. Passive survivability asks another question: how long can the architecture keep supporting its occupants after those systems disappear?
City Park Residence, Alterstudio, Austin, Texas, 2025 | image © Casey Dunn
THE a/c CAN STAY
Passive cooling has limits, and many designers view those limits as useful instead of inconvenient. A strategy that performs well in a hot-arid climate can behave very differently in a humid city. Thermal mass needs a way to release stored heat. Natural ventilation depends on useful outdoor conditions and acceptable air quality. Extreme heat can still demand active cooling for safety. The strongest contemporary houses treat passive design as a way to reduce the distance the air-conditioner has to cover.
Homes can bring responsibility back into walls, courtyards, openings and shaded thresholds. They can delay heat and divert it to create places where air can breeze through the rooms. Mechanical cooling can handle the remaining gap. As heat intensifies and electricity grids strain, that shared responsibility could become increasingly useful. Homes can employ the A/C later, use it less, and remain inhabitable for longer after it stops.
Bat Trang House, Vo Trong Nghia, Hanoi, Vietnam, 2021 | image © Hiroyuki Oki
This article is part of designboom’s MODES OF HABITATION chapter, exploring how the spaces we inhabit can reshape the ways we live together. Discover more stories rethinking domesticity, shared living, and the many forms a home can take here.
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