In hot cities, shade is a prerequisite for livability under high temperatures. While architects and urban designers have widely embraced the issue, its economic dimension is rarely discussed. Yet, shade is becoming a new scarce resource, raising the question of how it is shared and making it a political matter.
This exploratory note invites readers to anticipate how the delivery of urban services may change as global warming reshapes residents’ needs in the context of constrained local finances. How should the responsibilities of the municipality, the community, and individuals evolve? This note continues a reflection that began with the politicization of snow removal in cold cities: where does the white of cities go when the snow melts?1 Our initial hypothesis was that shade is to the sun what snow removal is to snow. Shade and snow, which conjure powerful imaginations and shape lifestyles, carry an anthropological dimension. However, just as it has always been easier to respond to cold weather than to hot weather—by lighting a fire or putting on an extra layer2 — shading is more complex than clearing snow. Snow removal is a service (like park and garden maintenance or public space cleaning), whereas shade is primarily infrastruc-ture, i.e., facilities and equipment made available for communal use. We will show that shade is becoming a new urban resource, that its provision has a cost, and that its value is rising, which may warrant engagement from municipalities.
To learn more about Shadow in La Défense, Paris, France.3
1. Shade is becoming a new urban resource
Awareness of the importance of “summer comfort” may soon give way to that of summer survival. The increasing frequency of heat spikes in heated cities makes shade an essential component of urban cooling and a prerequisite for access to public spaces.
Informative sign at the 2025 Biennale of Arts and the Ocean in Nice, France
1.1 Heated cities are experiencing increasingly frequent heat spikes
Global warming projections indicate a +4 °C increase in France by 2100, with the 44 °C threshold potentially reached or exceeded across all regions during extreme heatwaves, local spikes approaching 48 °C, and a tenfold increase in the number of heatwave days4. At the 2025 Architecture and Landscape Biennale in Versailles, the exhibition “Four Degrees Celsius Between You and Me”5 highlights the gradual migration of climate zones from the equator toward the poles at a rate of just over one meter per hour. “What was once the climate of North Africa will become the climate of tomorrow’s Europe; North Africa’s climate will become that of Equatorial Africa. […] The climate of Paris will resemble that of Italy’s Marche region—or even areas further south.” The exhibition invites us to draw inspiration from tradi-tional climate solutions while adapting them to different geographical contexts.
Cooling cities has become necessary due to their ongoing warming7. PStrategies for cooling outdoor areas include planting trees, which function as “natural air conditioners,” removing the asphalt from the streets, applying light-colored coatings, and humidifying the air and ground with water (fountains, misting systems, etc.). Shade also plays a key role, particularly in mitigating urban heat islands, as demonstrated by the “Paris Frais”8 and “Toulouse + fraîche”9 plans. In Toulouse, the municipality has installed numerous vegetated wooden pergolas and shade sails across many neighborhoods, which are projected to reduce temperatures by up to 5°C10.
The effectiveness of shade depends on how objects casting it reflect, absorb, and transfer the various wavelengths of solar radiation as energy. It also depends on the intensity of that light, the extent of the projected shadow (a telephone pole that casts a perfect shadow on a body in no way prevents the solar heating of surrounding surfaces), and the biology of the person receiving it11. The role of shade is therefore all the more important as it results from a combination of actions12.
Integrating urban heat island (UHI) issues into the early stages of an urban project
To learn more about “Integrating urban heat island (UHI) issues into the early stages of an urban project”13
1.3 Shade is a prerequisite for livable public spaces in heated cities
Shade is thus increasingly considered a way to keep public spaces accessible during hot weather. This is all the more essential as public space is once again becoming a sociable place, rather than merely a circulation space designed primarily for and by cars. Public spaces “to be lived” should be lived under all weather conditions, including extreme heat.
At the 2025 Venice Architecture Biennale, Bahrain’s Pavilion, titled “Heatwave”, was awarded the Golden Lion for best national pavilion. It reconstituted a “temporary shading pavilion” for places where indoor shelter is not possible, such as construction sites, and envisioned this type of solution as potential “thermal commons” and as sociable places in outdoor spaces. In this regard, there was a time when it was shade that shaped public spaces—for instance with plane trees in the towns of southern France or Rome’s basilicas14. “The great attraction of Mediterranean populations to their streets and squares largely stems from their thermal qualities.”15
Shade is therefore necessary to preserve—or even establish— the commoning of public spaces, and it allows people to move within them. Shading solutions must mitigate the impact of full daytime heat on pedestrians’ thermal comfort16. In an article with a manifesto-like title, “Shelter from the sun is a public resource,” Ghanaian-Scottish architect Lesley Lokko wrote that in African cities, from Kinshasa to Khartoum, “in places where midday temperatures can rise to over 40°C, the chance to sit—even 10 minutes—under a neem tree is more than simply welcome—it is essential.”17
2.Shade is created and maintained: shade provision has a cost
The sun cannot be created, but shade can, and it involves a strong material component. Shade provision can be broken down into several stages: its creation (urban morphology and equipment), its maintenance, its information layer, and its uses.
Urban design can be “bioclimatic:” street orientation and building heights in southern cities can create shade for sidewalks, squares, and buildings. “Vitruvius explains that Nero was mistaken to widen Rome’s streets, as their dimensions had been proportioned to create shade and channel the wind in just the right balance.”18 When streets run along a diagonal grid, all surfaces receive shade at some point during the day. And when building height exceeds street width, surfaces remain shaded for longer periods. Together, these two factors can minimize solar radiation on urban streets.
Medinas in North African towns and cities are thus designed to suit local climate conditions. For example, in Zenata, Morocco, Atelier Franck Boutté—recipient of Grand Prix de l’Urbanisme 2022, France’s national urban planning award—is working on an eco-designed new town of 500,000inhabitants whose urban layout harnesses the specificities of Morocco’s climate.“We therefore designed the overhangs to follow the sun’s curve and arranged them to ensure continuous shading.”19
Bologna, Italy, is also shaped by shade, but in a completely different way, with 62kilometers of covered sidewalks along buildings (portici) forming a vast labyrinth and allowing people to walk in the shade20. In the 13thcentury, numerous students flocked from all over Europe to the University of Bologna, and the city faced a housing shortage. In response, Bolognese residents added second stories to their houses and extended them over the streets. “Under papal rule, most Italian cities abolished the commandeering public space for private good. But perhaps in recognition of the benefits of shade, the Bolognese came to appreciate these odd projections. In 1288, the city not only legalized these ramshackle porticoes, but made them compulsory by statute. From then on, every landowner in Bologna’s busiest districts was ordered to furnish a covered public passage and maintain it for eternity at their own expense. Bologna’s porticoes became outdoor workshops where artisans, bakers, and carpenters worked in natural daylight without bearing the brunt of the sun. […] In most cities, it would be difficult to force a developer to meaningfully shade the sidewalk without getting anything in return. But in Bologna, it has been the order for centuries. The porticoes are what one critic called the physical expression of the residents’ social solidarity, ‘altruism turned architecture.’”21
To learn more about “map of Bologna’s 62-km-long porticoes”22
2.2 Shade creation: equipment
Should Bologna’s porticoes, which recall Singapore’s five-foot ways, be considered more equipment than an urban form? In any case, the “morphology” stage only applies to planned towns or new districts. Once a city has been built, one must work with what already exists. Features such as pergolas, jalousie windows, louvered shutters or mashrabiyas demonstrate the potential of shutters to ingeniously protect home interiors from the sun, combining shade, daylight, and airflow. Tree canopies, laundry strung up between buildings, and wooden “street canopies” provide outdoor shade, along with other solutions, which will now be analyzed across six categories pertaining to how shade is shared: natural/artificial, vernacular/technical, large-scale/small-scale, independent/networked, public/communal/individual, and stationary/mobile.
Jalousies
A jalousie is a blind with adjustable slats allowing occupants to look outside and to see without being seen. It is a key element of the architectural heritage of the French city of Lyon.
“Now the shadow of the column—the column which supports the southwest corner of the roof—divides the corresponding angle of the veranda into two equal parts. This veranda is a wide, covered gallery surrounding the house on three sides. Since its width is the same for the central portion as for the sides, the line of shadow cast by the column extends precisely to the corner of the house; but it stops there, for only the veranda flagstones are reached by the sun, which is still too high in the sky. […]
Now the shadow of the column—the column which supports the southwest corner of the roof—lengthens across the flagstones of this central part of the veranda, in front of the house where chairs have been set out for the evening. Already the tip of the line of shadow almost touches the doorway which marks the center of the façade. Against the west gable-end of the house, the sun falls on the wood about a yard and a half above the flagstone. Through the third window, which looks out on this side, it would reach far into the bedroom if the blinds had not been lowered. […]
Now the shadow of the southwest column—at the corner of the veranda on the bedroom side—falls across the garden. The sun, still low in the eastern sky, rakes the valley from the side.”
Robbe-Grillet, A. (1965 [1957]). Jealousy. English translationby R. Howard. John Calder.
NATURAL /ARTIFICIAL
Trees are one of the primary sources of shade in public spaces. When fully grown, they are particularly effective at cooling cities, as they not only block the sun but also cool the ambient air through evapotranspiration. Their impact is most striking in full sunlight: at 1p.m. the temperature ismeasured to be7°C lower under the trees23.However,youngtreessometimesprovide little shade, andplantingtreesmaynotbefeasible due tounderground networks.In such cases, artificial structures canbe particularly effective.
VERNACULAR /TECHNICAL
“Vernacular”, a term often associated with “picturesque,” primarily marks adaptation to a specific place, particularly its topography, climate, and locally available materials. The widespread adoption of air conditioning from the mid-20thcentury onward erased the need to consider the thermal qualities of a place. However, awareness is now growing of the limitations of this “modern” solution. For while air conditioners cool indoor spaces (including cars), they not only contribute to climate warming but also fail to cool public spaces. On the contrary, they exacerbate urban heat islands by releasing hot air into the streets24. This explains the relevance of “passive” solutions—which do not rely on external power sources. Often vernacular in nature, such solutions were showcased in several exhibitions at the 2025 Venice Biennale. Along the alley bordering the 300m-longCorderiebuilding,Urban Heat Chronicles presented an installation inspired by Venice’s narrow streets and their strung clotheslines. The “street skies” that are now flourishing are heirs to this hanging laundry, sometimes taking “participatory” forms (with residents of a street making the shade sails).
In contrast to vernacular approaches, some technical devices are not bound by local conditions. For example, the Australian document Shade Design for Public Space25 presents an array of shading solutions, many of which are manufactured by industry companies. Highlighting that “the provision of functional shade in public places holds great importance as Australians increasingly embrace broader uses of the public realm,” it identifies four types of shade: incidental shade (shade experienced when passing underneath), destination shade (the shaded area as the focal point), shade with a water-preserving design, and, lastly, shade sail. In France, corolla- shaped fiberglass canopies covered with climbing plants have been appearing in station forecourts. They have been developed by Urban Canopee, a company founded by graduates from the École nationale des Ponts et Chaussées engineering school graduates with the goal of deploying elevated green canopies that provide maximum shade while minimizing their ground footprint. This technical shading equipment contributes to the emergence of a new market where start-ups tackle climate change adaptation and become urban shade providers.
Shade can be created on various scales, using small or large equipment—or even on the scale of Brazil (see the Planetary Sunshade Foundation’s controversial project to launch a giant umbrella into outer space to cool the Earth26). In Seville, the Metropol Parasol (“Mushrooms of Seville”), inaugurated in 2011, is a vast wooden structure that casts shade over the Plaza de la Encarnación. It is 150mlong, 75mwide, 28mhigh,andcoversan area of more than 11,000m2.In Bordeaux, France, a monumental artwork serving as a shading structure accompanies the development of a new district on the right bank of the river. Designed by artist Leandro Erlich27 for the Cré’Atlantique fund, La Carte, À l’ombre de la ville (“The Map: In the Shadow of the City”)consists of fourteen 5m-tall aluminum treessurmounted byan approximately 400m2 canopy. Conceived as an urban forest, the ensemble forms an interpretation of Bordeaux’s map. Shading furniture is also appearing, such as the structures designed by AREP for station forecourts and sidewalks on nearby streets28.
La Carte, À l’ombre de la ville (“The Map: In the Shadow of the City”), Bordeaux, France, September 17, 2025, 10:43 a.m. (Leandro Erlich)
Shade can also be conceived as a network, with shaded pathways, for example. This concept of a network, of pathways, is important: if public authorities want to encourage walking in the city (to promote decarbonization and health), they need to provide walkways with shaded sidewalks or benches under trees that connect various locations in the city. For instance, the city of Paris has mapped out “cool pathways.”29 Similarly, in 2025, Marseille launched the Cool Noons initiative, which experiments with “the walkability of Mediterranean cities, tests concrete solutions to adapt to the climate emergency,” and provides cool pathways in summer30. Cities such as Madrid and Barcelona also implement “climate shelters.”
PUBLIC / COMMUNAL / INDIVIDUAL
Shade-protection solutions can be public, provided by local governments. In Lyon, a gigantic 6.5m-high, 1,500m2 sail structure was tested in Bellecour Square in summer2025.Suchequipment can also be communal, provided by a group of residents.Itcanbe individualas well—hats, caps, andsunshadeshave long proven effective forpersonalsun protection. In fact, the fashion industry is beginning toaddressthe issue, recalling how,in winter 2022,pufferjacket manufacturers boasted that their productshelped people stay warm and contributed to reduced gas consumption.
To learn more about “Chaude Couture (“Hot Couture”) project by Fabulism Studio at the “Four Degrees Celsius Between You and Me” exhibition”31
In Italy, Ferrara’s market demonstrates how large-scale shading, covering the entire market square, can be achieved by combining individual shading structures mounted on each stallholder’s truck, which retract into compact boxes. The market ends with a fabulous spectacle as each stallholder folds their awning away into wavelet-like shapes, joining in a hypnotic ballet of shadows32.
While shading solutions are often stationary, many are also mobile. Before the retractable arm was invented, shade sails on shop fronts were hung or hammered onto horse hitching posts or iron railings along the sidewalk, also covering the walkway33. In Venice, during the 2025 Biennale, the MIT Future Heritage Lab presented a pergola-shaped mobile structure alongside its Urban Heat Chronicles installations (mentioned above). Designed for pop-up events in public space (e.g., roundtables, dinners, small exhibitions, workshops, educational activities in school courtyards, etc.), it is mounted on wheels and can move based on the sun’s path34. The pergola thus transforms through its various uses.
2.3 Shade maintenance
While shade can be created, it also needs to be maintained. This applies to trees, green installations, and non-natural structures alike.
The management of public spaces is undergoing a major transformation due to their greening. But vegetation is more than a mere layer of green; it also has the distinctive quality of being alive35. This blurs the traditional dividing lines between those who design public spaces (e.g., planners) and those who maintain them (typically local governments). For example, planners increasingly remain involved during the initial years of a street’s maintenance, ensuring that plants are properly established. New practices in tree and tree-pit upkeep also give rise to new, more “spontaneous” urban aesthetics, sometimes challenging residents’ perceptions.
While green maintenance raises new questions, “artificial” equipment must also be maintained, including shade sails. Many companies offer maintenance services and provide extensive guidance on their websites, such as “Store your shade sail during the winter season” or “Check your sail’s fixtures and anchor points, as time and weather conditions—wind, rain, snow, hail, etc.—can affect them.” This maintenance issue may seem incidental. Yet, as shown by Jérôme Denis and David Pointille36, maintenance is political. For maintaining something involves deciding what constitutes its proper condition. “If you want the thing to be in proper condition, you maintain it in a condition that you consider suitable. And right away, a question arises: proper condition for whom?”
2.4 The information layer of shade
Just as access to public space increasingly involves access to information about public space37, access to shade requires map information tools, such as apps that indicate the most shaded pathways for walking or exercising. Information is therefore a means of adapting practices. It is intended not only for residents but also for professionals, such as photographers, or event planners: “Sun and shadow can make or break a daytime event. Too much sun exposure in the hot summer months will leave your audience breaking a sweat, and planning for enough shade might be crucial not only to keep them happy, but also to save energy expenses,” reads the Shadowmap app, which simulates shading in public spaces38. Weather forecasters could also play a leading role.
The information layer also features prominently in shading-related decisions at the early stages. Shadow modeling is both complex and precise, involving a significant real-time component. Artificial intelligence (AI) is therefore increasingly used to support shade provision. For example, Qui Veut Rafraîchir Sa Ville (“Who Wants to Cool Their City”), a company that develops cooling islands through micro-projects, uses algorithmic analysis of aerial photos to identify the plots of land most suitable for establishing them.
2.5 Uses of shade
Another way to shelter from the sun is to adapt practices, which may affect ways of life in newly heated cities. Sporting activities increasingly take place early in the morning or late at night, reflecting the importance of chronotopia for thinking about cities. In June2025, schools were closed due to excessively high temperatures.
As part of the Cool Noons project mentioned earlier, in summer2025thecity of Marseille circulated a questionnaire for residents and tourists to assess“the city’s attractiveness in the context of more frequent and intense heatwaves.” The questions illustrate how practices contribute to shade provision. The survey first asks: “Do you have any health condition that makes you more vulnerable toheat?” A subsequent question is: “To what extent are you willing to take a detour from the shortest route to the places you want to visit in order to follow a cooler pathway?” Finally, respondents are asked to complete the following statement: “Today, to get relief from the heat,” with one of the following five options: “I preferred shaded areas or spent more time in cooler indoor locations,” or “I sought water features like fountains,” or “I protected myself by drinking a lot of water,” or “I used fresh clothes and sun protective items (e.g.,a hat or sunglasses),” or “The heat made me plan my visit activities so as to avoid the hottest parts of the day.”39
France’s Pavilion at the 2025 Venice Biennale, titled “Living With,” can also be seen as a metaphor for these changing practices. As the pavilion building was closed for renovation and thermal adaptation work, the curators chose not to relocate the installation but to set it up beside the building, integrating it with the scaffolding and deploying branching paths that allowed visitors to walk down toward the canal through the trees—and their shade. This prefigures how, tomorrow, visitors will tour the Biennale’s pavilions mostly outdoors under cooling trees, rather than along the main avenue.
3. The value of shade is rising
Creation, maintenance, information, and uses—the various stages of shade provision show that it has a cost, which, against the backdrop of tightening financial constraints, contributes to its increasing scarcity. Depending on what is being shaded, the value of shade rises with each additional degree of warming.
3.1 The value of shade varies depending on location and time
“Nero’s house revolved perpetually, in imitation of the motion of the celestial bodies.” This quote from Pliny the Elder40 reminds us that shadows shift and must be appreciated according to the different times of day and year. “Shadow tables” in ancient times provided a rough estimate of the time, before being replaced by sundials, and later by clocks.
A shadow table used to enforce monastic rules, 12th century (allegedly)
Source: Pseudo-Beda, edited by Jean-Baptiste Delambre — In: Histoire de l’astronomie ancienne, I, p. 324
In urban projects, planners often collaborate with specialized consultants to conduct daylight and sunlight assessments in order to optimize building placement according to the intended outcome, such as creating more shade or, conversely, increasing solar input to heat bioclimatic buildings. The study of cast shadows may also take into account the “distant masks” of mountains. In any case, the warmer it gets, the greater the value of shade.
3.2 The value of shade varies depending on the body being shaded
The value of shade varies according to the sun’s path as well as the characteristics of the beneficiary, whether a natural person or a legal entity. “Expanding shade-giving infrastructure is a tool that will help cities reduce their thermal load by up to 50%. Access to shade for the vulnerable in our society – children, outdoor workers, the elderly, the homeless – is critical, quite literally the difference between life and death. Everyone needs and deserves access to shade. Shade is a civic resource, as well as an essential component of public and economic health,” writes the Public Improvement District of San Antonio, Texas, United States42. In Pantin, a northeastern suburb of Paris, “Heatwave Alert Plan” posters displayed on municipal billboards encourage people aged 65 and older or with disabilities to make themselves known.
3.3 The value of shade has long been measured in certain sectors
In the agriculture sector, the value of shade has long been studied for certain crops grown in hot countries. For example, as early as 1959, an article on “the role of shade in West Africa” confirmed that “light requirements vary according to the age of cocoa trees, as adult trees require more intense sunlight than young ones,” and that “in highly fertile or well-smoked soils, cocoa trees yield best without any shade. Conversely, in mediocre soils or in areas where crop management is limited to maintenance with no added fertilizer, full sunlight results in an imbalance between chlorophyll production, which reaches its maximum under these conditions, and insufficient mineral absorption, leading to the gradual decay of the plantation.” The article even provides details on how to investigate: “Any tree that would normally provide complementary resources, food or otherwise, must be considered suspicious, as the farmer always has a favorable bias toward that species.”43
In France, the impact of shade on cows’ heat stress is well known among milk producers. Cows are quite quickly affected by heat. They consequently produce less milk, which comes at a cost. Moreover, there are delayed impacts on cows’ metabolism in the following weeks and months, with animals producing less milk than usual and developing hoof problems due to poor blood circulation44. Providing shade, which can reduce livestock thermal load by up to 30%, is therefore essential in mitigating heat stress.
Some studies are also beginning to provide economic assessments of the health effects of heatwaves. A study conducted in 2022 by the French national public health agency, Santé publique France, estimated the health-related impacts of the 2015–2022 heatwaves to range from €22 billion to €37billion, depending on the methodology used. The study considered the economic costs of three impacts—healthcare utilization46,excess mortality,andloss of well-being through activity restriction47—as well aseconomic valuations of human lives.
3.4 Toward a reversal of public space value?
Cacao and milk may end up in a coffee cup. In its early 2025 report on “outdoor seating areas located in the public realm” in Paris, the French Court of Audit highlights sunshine as a factor that increases the value of outdoor seating areas: “Substantial climate changes confer increasing attractiveness, and therefore commercial value, to outdoor seating areas located in the public realm during the summer season.”48 It is also worth recalling that a dozen years ago on the Champs-Élysées Avenue in Paris, areas on the sunlit sidewalk (even-numbered side) had higher rental values than those in the shade (odd-numbered side), sometimes by a 2:1 ratio.
Extract from the French Court of Audit’s report on outdoor seating areas in Paris – 2025
The principle that the public realm is not free of charge is well established
The possibility of using a public realm asset for private purposes beyond the right of use granted to all constitutes a dispensation (ArticleL.2122-1 of the French General Code of Public Property, CG3P). Consequently, ArticleL.2125-1 of the CG3P establishes the principle that any private occupancy or use of the publicrealmshall be subject to the payment of a fee. The law strictly regulates the situations in which exemptionsmay be granted, limiting them to six cases in which public interest justifies free-of-charge occupancy.
The amount of the fee shall take into account the benefits conferred on the beneficiary
The amount of the fee payable for occupying the public realm shall be freely determined by the local government’s deliberative authority. Under Article L2125-3 of the CG3P, it shall “take into account the benefits of any kind conferred on the holder of the authorization.” In the absence of detailed wording, lawmakers certainly intended to grant the public realm manager considerable latitude in this matter.
However, the manager should act with caution and comply with certain guidelines: setting too low a fee may constitute illegal aid to business real estate or a disguised subsidy. Conversely, the fee for occupying the public realm shall be lower than the commercial rental price, as the lessee is placed in a precarious, revocable situation that does not confer real rights.
The local government may use and combine different elements: occupied surface area, use, situation, business nature, and profitability of the establishment, with the fee indexed to its sales revenue.
But will this still be the case in a 50°CParis?49On the one hand, the value of sunshinewill always exceed that of shade,sinceshade can be created, whereas sunshine cannot. On the other hand, the warmer it gets, the greater the value of shade. Thisholdstrue at the scale of adwelling,andeven more so at the scale of a sidewalk, a street, or a square. Shade has economic value and can be privatized, sold, or rented—the highest prices requested for shaded seats in Spanish arenas or for beach parasols in Italian resorts are typical examples50.
“Did you know that restaurants with outdoor seating can increase their revenue by up to 30% during peak seasons?”boasts a U.S. shade structure manufacturer51. Tomorrow, the benefits, as cited by the French Court of Audit for setting the fee’s amount, will most likely have to integrate the availability of natural shading. Or will we see all outdoor seating areas covered, enclosed, and air-conditioned by then?
Shade is also a matter of social justice. In Los Angeles in 2019, as authorities deployed cover to hundreds of bus stops and planted 90,000trees,the city’smayor insisted,“Shade is increasingly seen as a precious commodity, as the crisesof climate change and inequality converge.”52 He added, “Shade is an equity issue,” aligning with some French elected officials who call for a “right to shade,”53 while more and more shade indices are being developed—one of the advantages of shade is that it can be easily measured.
In Shade: The Promise of a Forgotten Natural Resource,54 published in July2025, American journalist Sam Blochanalyzesthe paradigm shiftin which shade has gonefrombeingdisregardedtobeingnecessary. He revisits how the search for shade has historically shapedurban planning in hot cities andexaminesthe case of Los Angeles to show how considerationsofsecurityorrelatedtothe primacy oftheautomobilehinderaccess toshade for all. Hecitesthe example of a bench that residents had installed under a tree near a bus stop, which officials prohibited, claiming it could compromise sidewalk safety and security. Yet, when temperatures soar, the definition of public safety could include protection from the sun. “For decades, L.A. police have discouraged trees because their shade is a magnet for gathering and their umbrage interferes with surveillance. More recently, in the throes of a homeless crisis, city staff and law enforcement have removed and denuded trees to control the conditions on the street,” Bloch writes.
Mike Davis55 and, more recently, other researchers56 have addressed the political dimension of shade, particularly in terms of social justice. After considering heat-related victims and the unequal distribution of shade trees in wealthy and poor neighborhoods of Los Angeles, Davis called for a “politics of shade,” asserting that “shade has become an inalienable human right.” Following in his footsteps, some researchers have advocated for the development of a theoretical approach of shade, particularly from a social perspective and taking into account its conflict dimension57.
Ghanaian-Scottish architect Lesley Lokko (mentioned earlier), who states that “shelter from the sun is a public resource,” notes that in recent years, “accompanying the rapid and explosive urbanisation patterns across Africa, shade has increasingly become under attack. This war on shade is fuelled on the one hand by rising land values, and on the other hand, weak planning governance.”
4. What if shade provision became a new local public service?
Shade is thus becoming a new urban resource. The risk is that it may grow increasingly scarce, because the resources required to produce and maintain it (soil and water for trees, and public finances in general) are in limited supply. At the same time, its value is rising, both economically and in terms of access to public spaces, public health, and social justice. Access to shade is increasingly an issue of social equity. Depending on the place and the level of exposure to urban overheating, shade could be to the 21stcentury what drinking water and clean air were to the 20thcentury58.
Consequently, shouldn’t shade become a local public service, one of whose three core pillars is precisely the principle of equality? Today, shade is provided sometimes on an individual basis, sometimes by the community, but without any explicitly stated shade policy. The term “local public service” is used here in a broad rather than strictly legal sense, to suggest that local governments could take on a more active role in providing it. Seven exploratory scenarios are presented, with the aim of encouraging elected officials to engage in the issue. How could a shade provision service be implemented? In the first four scenarios, responsibility for shade provision falls to local governments under different models. The next three are more “shade commons” scenarios, in which the role of local governments is less to provide shade than to manage its provision by a mix of public authorities, private operators, and individuals. These scenarios are primarily heuristic in purpose.
4.1 Toward public shading places? Treating shade like outdoor public equipment
One could extend the Bahrain Pavilion’s proposal for “thermal commons” and envision local governments not only providing shade in public spaces but also developing outdoor, open-air public shading equipment.
Outdoor shading structures already exist in some locations, but this proposal would aim to further assert their status, their role as destinations, the thermal function of these new equipment-places, as well as their formal significance. An analogy can be drawn with public baths in ancient Rome, as discussed in Thermal Delight in Architecture. Originally, baths were a luxury only the rich could afford. Then Roman builders (that is, private operators) constructed bathhouses accessible to the public for a small fee, and some evolved into genuine, “warm” social gathering places. Later, Roman emperor Agrippa established public baths, named after him, which were to be free in perpetuity, serving as tangible evidence of the ideal that all Roman citizens were entitled to benefit from the empire’s opulence. “In their dazzling marble grandeur [the Baths of Agrippa] were not only the splendid ‘Palace of Roman Water,’ but above all the palace of the Roman people, such as our democracies dream of today.”59 So when will we see palaces of shade in French cities?
4.2 Toward the widespread adoption of public street shading? Funding shade like sidewalks
The transformation of café and restaurant outdoor seating areas over just a few years in France is striking. Immediately after the first COVID-19 lockdown in 2020, cafés and restaurants were authorized to extend their outdoor areas onto sidewalks and parking lanes, and their numbers increased rapidly. At the time, these areas allowed people to remain in the open air and helped limit the spread of the virus. Once the pandemic subsided, their numbers continued to grow on and along sidewalks, as people sought outdoor, sunlit environments. Already, at certain times of the day in summer, they allow us to enjoy shaded outdoor spaces. Tomorrow, they will no doubt provide shade to café customers, but they could also serve more broadly as street shading solutions, particularly for areas frequented by pedestrians, who remain stifled by the heat despite their caps—the sidewalks. Coupled with the example of Bologna’s porticoes, this transformation invites an analogy between street shading and the generalization of sidewalks in Paris in the mid-19th century. Sidewalks began to appear as early as 1781. They were initially funded by street residents and most often discontinuous, since each resident funded their own section. However, sidewalk development soon became essential, particularly in response to the dirtiness and congestion of streets. This led to the passage of a law in June1845 “pertainingto the distribution of sidewalk construction costs.” Where sidewalkswererecognizedas beingofpublic interest by thecityadministration,the lawallowed for equal shared funding: half covered by the municipality and half by residents. Subsequently, Baron Haussmann, who became Paris’s prefect eight years later, took pride in having promoted the development of sidewalks by reducing the share paid by residents from half to one third60.
The debates surrounding the 1845 law thus raised the question of whether sidewalks should be considered primarily as an individual amenity, to be funded by each resident, or as a public-interest infrastructure, to be funded by the municipality. A similar question may arise regarding shading facilities, particularly shaded outdoor seating areas or awnings located on sidewalks along building facades: should each piece of shade be funded individually or collectively? Today, seating areas on or along sidewalks are funded by restaurant owners. Yet one could imagine them being supported by the local government, combining interest for continuous—rather than discontinuous—shading along pedestrian pathways (thereby limiting urban heat islands) with aesthetic considerations. Terraces along the Champs-Élysées constitue an early expression of this approach, with harmonized designs, here at the scale of a collective of business owners. Outdoor seating areas and awnings could be mobile and retractable. They could be funded through a higher occupancy fee, reflecting the greater value of shade.
4.3 Toward a public shade distribution service? Treating shade like water or waste collection
Although water is available in nature, there are costs associated with the services needed to harness it, including pumping it from its natural environment, making it safe to drink, and delivering it to the tap. Similarly, shade entails production and management costs, as seen with the different stages of its provision. It is then tempting to imagine, by analogy, what a public service of shade distribution might be. For water distribution has not always been a public service. In 1778, the Périerbrothers, who were granted letters patent by King LouisXVI to distribute drinking water in Paris,“had to develop machines to lift water from the Seine and install distribution pipes beneath the streets, along with utility holes. From these points, the wealthiest households equipped with an in-house reservoir were supplied by water carriers. For lower-income households, the installation of public distribution fountains was planned. The system was still a long way from universal service.”61 The era was that of a “pre-hygienist context in which the issue of water supply had not yet become a political matter of primary concern to the local community as a whole,” and “public authorities viewed the establishment of these companies favorably. […] They were often willing to grant them special arrangements so that they could carry out their operations, expecting them to improve the amount of water available to residents in cities where conditions were unsatisfactory, but without considering this a matter of urgency or absolute necessity. Admittedly, more water was needed; nevertheless, it was not a priority. This probably explains why these private water companies were able to establish relationships with cities and set up operations there so easily, often under terms disadvantageous to the municipalities, which attached little importance to the matter—there were few subscribers, alternative supply methods were widely used, and the network was still far from indispensable for providing residents with water.”62 Then, from the 1830s onward, water became a key issue for many towns and cities, driven by urbanization, industrialization, and the rise of hygienist ideas following the 1832 cholera epidemic. More and more municipalities came to regard water networks as essential infrastructure and decided to resume direct management of their water services.
Similarly, some municipalities could establish shade distribution as a public service, operated either directly through a public company or through a delegation contract, with infrastructure consisting not of buried pipes but of the various shading equipment mentioned above and their associated maintenance services. With regard to how this service would be funded, a more fitting analogy might be drawn with waste collection services. Indeed, in France, public water supply and sanitation services are now administratively classified as “Industrial and Commercial Public Services” (SPICs) and must therefore be funded primarily through fees paid by service users. By contrast, waste collection services can be funded either by users, when financed through the Household Waste Collection Fee (REOM), or by tax revenues or subsidies, when financed through the Household Waste Collection Tax (TEOM). In the former case, the fee is proportionate to the service provided, rather than to the taxpayers’ means, as in the latter.
4.4 Toward a public shade maintenance service? Treating shade like snow removal
Another scenario consists in an analogy not with water supply or household waste collection but with snow removal as practiced in Montreal. A public service of shade maintenance would then concern not the “infrastructure” element but only the “maintenance” one, including maintenance of shade trees, shading sails, and other equipment.
Snow removal in Montreal is an essential service whose provision conditions have changed over time. In the 19thcentury, responsibility for snow removal lay with residents (as is still the case in many other cities). It was only from 1905 onward that the municipality decided to take charge of it. Montreal’s specificity in terms of snow removal stems from the fact that its downtown area is particularly dense, that, as a result, there is little room for snow storage, and that temperatures are too cold to let snow melt naturally. Snow is therefore transported to landfill sites outside the city. However, climate warming is now causing freeze-thaw cycles, which make snow removal from sidewalks considerably more costly, while municipal finances are already under severe strain. In this context, in February2024—duringQuebec’ssecond warmest winter since temperature recordsbegan—snowbecameapoliticalissue: if snow cannot be cleared simultaneously from all sidewalks, bikeways, and roadways, or ifthoseshouldmaybenot be cleared/maintained every day, itis because such operations are costlyandimposetrade-offs. “Snowremoval” can be replaced with “maintenance.” What should be the “value proposition” or the ends of a [maintenance] policy? Who does it primarily target? How is it what costs and with what resources? A simple observation of sidewalks in Montreal and, for example, sidewalks in New York City highlights the distinction between those [maintained] by the local government and those maintained by residents. In Montreal, [maintenance], which is the municipality’s responsibility, is relatively uniform, whereas in New York, where it falls to residents, the section of sidewalk in front of one house is [maintained] differently from the adjacent section.
Similarly, one could imagine a future shade maintenance service that would vary between municipal responsibility and individual responsibility, depending on the city and, within each city, on the streets considered.
The diagram shows that today, snow removal in Montreal is carried out by the municipality, except on a few alleys. In New York City, snow is cleared from sidewalks by residents. Tomorrow, in Montreal, snow removal on all alleys may be left to residents, while the municipality would continue clearing snow from sidewalks on secondary streets, albeit at a reduced level of service (e.g., only every other sidewalk or with longer response times).
4.5 Toward an ecosystem approach to shade
The following three scenarios are even more exploratory than the previous ones. They are outlined briefly.
TOWARD SHADE COMMONS? TREATING SHADE WITH A CITY-FLOOR APPROACH
“City-floor” (rez-de-ville)63 approaches encourage us to view the ground floors of buildings as extensions of the street, and therefore as extensions of the sidewalk, rather than as the base of the building in which they are located.
For example, in Lyon, vacant ground floors are used to accommodate bicycle shelters that would otherwise occupy sidewalks. In a similar way, shade commons could consist in providing access to shaded spaces for all, whether public or private: interiors of shops or building hallways, where people could take refuge for a cooling moment, or “shaded shelter areas,” such as museums that open during heatwaves.
This “shade-floor” approach invites us to inventory and characterize the legal status of all intermediary shade places, such as café outdoor seating areas, Bologna’s porticoes, or house porches—at the 2025 Venice Biennale, the United States Pavilion, titled “American Porch of Life,” was devoted precisely to this architectural figure64.
The search for shade blurs the traditional dividing line between inside and outside, and often, consequently, between public and private. It recalls the 1748 Nolli map, on which public spaces and building ground floors accessible to the public are depicted in the same way—at that time, indoor shaded spaces in churches and palace courtyards were considered public spaces.
TOWARD SHADING AS A SERVICE? TREATING SHADE LIKE MOBILITY AS A SERVICE
The #GourdeFriendly project, implemented in 2025 by the city of Marseille along its cooling pathways, aims to enable residents and visitors to refill their reusable bottles with drinking water for free at partner businesses, which also helps reduce plastic waste65. The network was initially launched with 32businesses, displayed on the mobile app and on the city’s official tourist routes. By mid-year, it included more than 50refill spots scattered across the entire city, with the goal of reaching 100establishments by the end of 2025.
The project, which partly adopts the “city-floor” approach mentioned above, invites us to view shade as a component of a service package for residents, which would be provided or coordinated by the municipality through an ecosystem of both public and private operators, similar, for example, to Mobility as a Service (MaaS)66. A MaaS-like offer adopts a “user-centered” approach, starting from people’s practices and their desire to travel from pointA to pointB. Itallows the combination ofseveral services, including public transportation, carpooling, car sharing, cycling, private hire taxis, and route information, all under a single payment system. In the same way, one could imagine shading service packages. Shade could also be integrated into other service packages, such as tourism or mobility packages. This type of initiative encourages thinking in terms of ecosystems, that is, groups of heterogeneous and interdependent stakeholders that local governments can steer in various ways.
Just as porticoes, canopies or awnings67 are private sources of shade that provide a public benefit, examples of one building being shaded by another highlight the fact that shade is widely shared68. Shade frequently functions as an externality, referring to the situation in which an economic agent’s activity produces an external effect by providing a third party with a utility or benefit free of charge, or, conversely, causing harm or damage without any compensation.
One could then imagine local authorities valuing this type of externality, similar to the mechanism implemented under Paris’s bioclimatic Local Urban Plan (PLU): “The innovative nature of the bioclimatic PLU is notably exemplified by its mechanism for valuing the positive externalities of projects. Valuation may apply to three domains (biodiversity and environment, planning, and energy efficiency and reduced consumption) and nine criteria (proportion of unbuilt/open area, proportion of plant-covered building surfaces, rainwater reuse, social mix, variety of urban functions, ground-floor vibrancy, building energy performance, summer comfort, and carbon impact reduction). Beyond the requirement to comply with the provisions of Chapters1–7 of the regulation, granting a construction permit willrequire overperformance from theprojectunder reviewin at least three of these criteria across two different domains.”70
The magic of shade: it makes dwarves look taller
Neighboring the Villa Rotonda designed by Palladio, near Vicenza, Italy, the Villa dei Nani takes its name from the 17 dwarf statues now located on its outer wall. Legend has it that a castle once stood on this hill, where a dwarf princess lived in reclusion. She spent her childhood in an entirely tailor-made world: from furniture to objects to servants, everything was of small size, so that she would never become aware of her difference. But one day, as she leaned over the castle walls, her eyes met those of a handsome prince on horseback. They fell in love, and that very night the prince returned and climbed the outer wall to meet her. Yet when he realized how different the princess was, he screamed and took flight. Upon realizing her deformity, she resolved to kill herself, and her death caused the grief-stricken dwarves to turn to stone. At night, there is no shade.
Conclusion
Long perceived negatively—despite works such as In Praise of Shadows by Jun’ichirō Tanizaki and In Praise of Darkness by Jorge Luis Borges—shade is becoming vital in heated cities, and access to shaded public spaces is emerging as a democratic concern. With urban economy understood as the art of sharing scarce resources so as to live together in ever-greater harmony, the sharing of shade is becoming political. The issue is significant in itself, but above all it highlights the need to reflect on how the evolving provision of urban services in the context of global warming and constrained local finances.
Heschong, L. (1979). Thermal Delight in Architecture. MIT Press.
Left : September 12, 2025, 9 a.m., view from an office located in the southern pillar of La Grande Arche de la Défense, Paris. The monument is often used as a source of shade, but since it is protected by copyright, we have chosen not to reproduce an image of it here.
Le climat futur en France : à quoi s’adapter ?Météo-France.
This study was conducted by Julien Bigorgne under the supervision of Paul Baroin. The urban heat island (UHI) issue should be integrated into the earlies stages of urban project design, alongside all other aspects such as landscaping, networks, traffic patterns, building square footage, etc.
Rahm, P. (2020). Histoire naturelle de l’architecture. Pavillon de l’Arsenal.
Heschong, L. (1979). Thermal Delight in Architecture.
Un parasol géant dans l’espace pour refroidir la planète ?France Inter. https://www.radiofrance.fr/franceinter/podcasts/un-monde-nouveau/un-monde-nouveau-du-mercredi-27-decembre-2023-8355397.
Creator of Maison fond (“Melting house”), installed in front of Paris’s Gare du Nord station—one especially loves his fake swimming pool, his climbable facades of apartment buildings or mansions, his trompe-l’œil staircases, and his mirrors that aren’t really mirrors are especially admired.
Adélaïde L, Chanel O, Pascal M. Health effects from heat waves in France: an economic evaluation. Eur J Health Econ. 2022;(23):119–131. https://link.springer.com/article/10.1007/s10198-021-01357-2. “The analysis included direct medical costs (outpatient clinic visits, emergency department visits, and hospitalizations), indirect costs (loss of production), and these intangible components that represent the loss of well-being and quality of life for the patient and his or her family (grief, fear, pain, lost time, etc.).”
“We approached loss of well-being through activity restriction associated with the red heatwave level. The triggering of the ‘red’ level results for example in warnings to avoid travel and physical activities, working from home, and the cancellation of various events. Moreover, from a physiological perspective, the temperatures during ‘red’ days are likely to lead to mild symptoms such as fatigue, cramps, decreased cognitive function in the largest part of the population.”
“As a result of climate change, outdoor seating areas can be used over an increasingly long period during the year.” “On average, for the reviewed period, from 2017 to 2023, the accumulated hours of sunlight in Paris between April and October—the summer outdoor seating operating period—exceeded the long-term average for the same months from 1991 to 2021 by 254.3hours (1,525.3hours of sunlightcompared with a long-term average of 1,271 hours).” Ville de Paris—Les terrasses implantées sur le domaine public. (2024). Île-de-France Regional Audit Chamber. https://www.ccomptes.fr/sites/default/files/2025-01/IDR2024-51.pdf
Gabellieri, N. (2025). A place in the shade? Shaded spaces as a domain of geographical research: a literature review (1990–2024). GeoJournal 90, 26. https://doi.org/10.1007/s10708-024-11278-1
Gabellieri, N. (2025). A place in the shade? Shaded spaces as a domain of geographical research: a literature review (1990–2024). GeoJournal 90, 26.
Mike Davis’s article highlights the relationship between the presence of shade trees and marginality in urban districts of Los Angeles, emphasizing the direct link between shade and income. This perspective has inspired numerous studies assessing the location of shade trees and, more broadly, the presence of shade in contexts of marginality or exploitation. Several studies have documented the limited access to shade resources for the most vulnerable segments of the population. The presence of shade trees or of other heat- and sun-protection solutions is often perceived as a sign of spatial inequality, even influencing real estate prices and processes of gentrification.
According to UCLA professor Kelly Turner, shade could represent the next long-term public health investment in the United States. What drinking water and clean air were to the 20th century, shade could be to the climate-changed 21st century. Bloch, S. (2025). Shade: The Promise of a Forgotten Natural Resource.
J. Carcopino, cited in Heschong, L. (1979). Thermal Delight in Architecture.
Baraud-Serfaty, I. (2023). Trottoirs ! Une approche économique, historique et flâneuse. Éditions Apogée, reissue in 2026.
Exhibition tour. (2025). Porch: An Architecture of Generosity. https://www.porchusavenice2025.org/exhibition-tour. The exhibition features the following quote by 19th U.S. President Rutherford B. Hayes: “The best part of this house is the veranda. But I would enlarge it. I want a veranda with a house attached!”
In The Front Porch as Stage and Symbol in the Deep South (1985), Perry, R. L. writes, “The sitting porch, which is widespread on Southern houses, testifies to the influence of the hot and humid climate of the region on pre-modern lives and social habits. Did technological developments render the veranda anachronistic in the twentieth century? Americans did not consciously decide to abandon front porches in the 1950s, but that was what happened. Over the past three decades streets had been widened and congested with smelly, noisy automobiles, so residents across the country went inside for television and climate control, and they retreated to the backyard patio for casual social gatherings.”
Additionally, all things being equal, shaded and cooled outdoor areas contribute to summer comfort in dwellings. Shade is shared—or enjoyed at the expense of one’s neighbor. Until 2019, Los Angeles planners required a shadow analysis of any building that loomed five stories over the surrounding landscape, fearing the 100 ft shadows that could darken nearby gardens and sun-bathed patios. See Bloch, S. (2025). Shade: The Promise of a Forgotten Natural Resource.
The picture also illustrates the significant role of “angle poetics” in shaping the urban layout of Ferrara’s new town during the Herculean Addition. See https://www.ibicity.fr/les-trottoirs-de-ferrare/.
