Paris Apartments Were Built for a Climate That No Longer Exists

Paris Apartments Were Built for a Climate That No Longer Exists

The heatwave is turning older housing stock into a public-health infrastructure problem.

Reuters reporters Michaela Cabrera, America Hernandez, Sam Tabahriti, Simon Jessop, Ilze Filks, Emma Pinedo Gonzalez, and Angeliki Koutantou reported that homes in Paris and London are failing under extreme heat because much of the housing stock was designed to retain warmth, not release it. In Paris, a 9-square-meter attic flat beneath zinc rooftops became an oven after several hours of sun as the city hit a June record of 40.9 degrees Celsius, or 105.6 degrees Fahrenheit.

Housing policy now has to answer a climate problem it avoided for decades. Older European homes were built around winter logic: trap heat, conserve energy, and protect residents from cold. That design choice made sense inside the climate those buildings were built for. It becomes dangerous when summer heat arrives earlier, lasts longer, and pushes indoor temperatures beyond what people can sleep, work, or recover inside.

The mechanism is physical. Heat enters through windows, roofs, walls, and exposed upper-floor spaces, then stays in apartments with weak ventilation and limited cooling. Residents respond with fans, wet towels, aluminum foil, and improvised shade. Those tactics may lower discomfort for a few hours, but they do not retrofit a building. They move the burden of adaptation from the state and property owners to tenants trying to manage rooms that no longer function as they were supposed to.

Air conditioning is available to some households, but it cannot be the whole solution. Reuters reported that only about 25 percent of European households have air conditioning, compared with about 90 percent in the United States and Japan. Expanding air conditioning everywhere would also add electricity demand and release waste heat outdoors, worsening the urban heat problem if cities do not redesign buildings and streets around passive cooling. Cooling becomes another class divider when higher-income households can buy relief and everyone else inherits the building’s limits.

The more durable tools are practical: better shade, reflective surfaces, stronger ventilation, roof overhangs, recessed balconies, urban trees, and building standards that treat summer comfort as habitability. Anna Mavrogianni of University College London told Reuters that keeping heat outside is more effective than trying to cool a home after it builds up indoors. That shifts the policy debate from consumer gadgets to building regulation. It also puts responsibility back on the institutions that approve, finance, renovate, and inspect housing.

Power moves through the walls. Landlords, developers, co-owner associations, and governments control most of the choices that determine whether a home can handle heat. Tenants and lower-income residents absorb the health risk when those choices are delayed. A person living under a poorly insulated roof cannot individually solve the physics of the building.

The labor consequences are already visible. Reuters described residents struggling to focus at work, weighing whether to commute to an air-conditioned office or remain inside overheated homes. Heat turns domestic space into a productivity constraint, especially for workers whose jobs moved home during and after the pandemic. A poorly cooled apartment becomes a workplace hazard without being recognized as one.

The next housing crisis in dense cities may be measured in indoor temperature as much as rent. Apartments that were legally acceptable in one climate can become functionally inadequate in another. If cities do not make cooling standards part of housing policy, the market will sort residents by who can pay for livable air and who is left to improvise through the next heatwave.