Photo: Michael Busch / Unsplash (CC0)
Heatwaves worldwide are getting longer and hotter. How can people and cities best protect themselves from these high temperatures? The answers range from green façades to cooling systems from the underworld.
Rammed earth blocks made from compacted earth have been used in construction for millennia. Lately, their sustainability and natural insulating and cooling properties are attracting the attention of architects. The blocks can be made with minimal carbon impact and can simply return to the soil at demolition
Source: The Guardian
An age-old construction method is finding new fans in India’s modern cities. Architects are reimagining traditional materials like mud plaster, sal wood, bamboo, and lime for contemporary apartment buildings, which can keep buildings about 10°C to 15°C cooler than outside temperatures.
Source: Reasons To Be Cheerful
Scientists in Singapore have developed a cement-based paint designed to cool buildings in humid climates by evaporation, much as bodies sweat, as well as by reflecting light. The paint holds water captured from the air surface and releases it slowly over time and, in tests, allowed 30-40% less electricity use for air conditioning.
Source: Science News
Passive House standards, known for creating super-tight building envelopes that eliminate the need for central heating and cooling, are quickly moving from a niche concept to a common solution. These standards are making a splash in new building codes across states like Massachusetts, Illinois, and Washington.
Source: Energy News Network
Researchers at Delft University of Technology have developed a special moss-friendly concrete and a self-adhesive gel to cover façades with moss and solve the problems encountered in the past.
Source: Parametric Architecture
A London startup is developing moss-covered wall panels designed to help clean urban air, reduce noise and add greenery to dense city spaces. The company Alive Labs says moss can serve as both a functional and natural form of urban infrastructure.
Source: Reuters
Research on the effects of tree canopies in cities suggests that they can help cool buildings and streets by up to 18°C, but only with layered planting. This includes tree cover but also shrubs and ground cover together.
Source: The conversation
The “Miyawaki method” involves planting small forests in urban areas. Due to the lack of competition from other trees, these “tiny forests” can mature in 10 years instead of 100. Now they are being planted across Scotland.
Source: BBC
Short on space and keen to hit its climate goals, Vienna is converting streets and parking spaces into parks, gardens and tree-lined areas. The move is intended to create more room for people to enjoy the city while also cooling neighbourhoods and improving overall air quality.
Source: Deutsche Welle
The almost 5,000-acre green belt around the capital began in the 1970s with the goal of reforesting land lost to desertification. It has met its original goals and in recent years expanded its mission to cooling and feeding the city. Climate migration has caused the city to grow rapidly, but residents, including those displaced from rural farming, can claim plots and garden up to six beds.
Source: The Guardian
Started as a competition during the pandemic to encourage the creation of wild spaces in urban areas, ’tile whipping’ is now a national pastime and social activity where neighbours and friends join forces to replace large swathes of pavement tiles with gardens and greenery.
Source: Reasons To Be Cheerful
The surfaces of car parks often get very hot when in direct sunlight and can’t cope well with storm runoff. Now, groups across the US are looking to more sustainable options, such as porous concrete panels and native plants to make the areas cooler and less prone to flooding.
Source: AP News
From wind corridors in Stuttgart that channel cool air from meadows and orchards outside city limits to buildings in Singapore designed to creatively let cool breezes travel though, BBC journalists from People Fixing the World visit cities that are finding solutions to urban heat using wind.
Source: BBC News
In a climate experiment modelled in part on ancient Persian water channels that transported water from deep aquifers, Seville, Spain, has built an underground system of aqueducts to help beat the heat. The pipes of CartujaQanat have run from March to October since 2022, helping keep one of Europe’s hottest cities cool.
Source: Next City
Paris’ cooling system has 120 km of underground pipes distributing chilled water from the river Seine to museums, offices, hospitals, schools and other public buildings including the Louvre and the Grand Palais. Instead of thousands of individual air-conditioning units, cooling is produced centrally and shared across the city like a utility. Now the city is planning to triple the number of underground pipes.
Source: The Guardian
This particular type of thermal energy storage, in which tanks of ice sustain a network of cold-water pipes keeping rooms at cooler temperatures, is being added to buildings across the US. The method reduces electricity usage and lowers the overall strain on the energy grid.
Source: AP News
Researchers at Virginia Tech have developed a 3D-printed evaporative cooling system made of hollow clay columns that can cool the surrounding air by up to 10 degrees Fahrenheit. Filled with water and sand, they cool by evaporation when warm air passes through the porous exterior of the clay.
Source: Good Good Good
India’s relentless summer heatwave has sparked a resurgence in an age-old technique of chilling water in terracotta vessels. This traditional method, once confined to household use, is now inspiring adaptations like modern cooling towers and architectural screens to combat the extreme temperatures.
Source: BBC News
The Laikipia Integrated Housing Project uses local materials like soil, cow dung, timber, and grass, as well as older local building traditions to create compressed earth blocks. The resulting thick, earthen walls are keeping homes and schools cooler in the Kenyan drylands as temperatures rise.
Source: Climate Home News
Climate change and urbanisation in the capital of Sierra Leone has driven temperatures as high as 40ºC, with high humidity on top of that. A programme installing heat-reflective mirrored sheets has shown initial results of cooling up to 6ºC.
Source: The Guardian
Luis Cassiano is the founder of Teto Verde Favela, a nonprofit which helps people build their own green roofs. Cassiano shows the community a lightweight, sustainable and affordable way to cool homes without burdening electrical grids or relying on expensive fans and air conditioning.
Source: NPR
As demand for air conditioning rises, Irish engineers are developing a technology to eliminate climate-harming HFC gases, while architect Francis Kéré uses traditional materials to avoid AC altogether in Burkina Faso.
Source: BBC News
Heat negatively impacts learning, but architects, designers, and planners are preparing for a warmer future with school designs that cool passively. Clay structures, lattice walls, aerating roofs, and geothermal cooling are some of the strategies being put to use.
Source: Context
As India swelters, one eco-school serves as a refuge from dangerous heat and sandstorms. The building, which hosts 400 pupils, is powered by rooftop solar panels, among other features.
Source: Euronews
John Boland and Chris Bryant use their garden to shade their house from Australia’s hot summers – and it helps feed them as well.
Source: The Guardian
