The number of vacant houses in Japan has surged to a record high of nine million – more than enough for each person in New York City – as the east Asian country continues to struggle with its ever-declining population.

Abandoned houses are known in Japan as “akiya” – a term that usually refers to derelict residential homes tucked away in rural areas.

But more akiya are being seen in major cities, such as Tokyo and Kyoto, and that’s a problem for a government that’s already grappling with an aging population and an alarming fall in the number of children born each year.

“This is a symptom of Japan’s population decline,” said Jeffrey Hall, a lecturer at Kanda University of International Studies in Chiba. “It’s not really a problem of building too many houses” but “a problem of not having enough people,” he said.

According to figures compiled by the Ministry of Internal Affairs and Communications, 14% of all residential properties in Japan are vacant.

The numbers include second homes and those left empty for other reasons, including properties temporarily vacated while their owners work overseas.

They aren’t all left to ruin, like traditional akiya, whose growing number present a range of other problems for the government and communities, experts told CNN.

They include stifling attempts to rejuvenate decaying towns, becoming potential hazards due to the lack of maintenance, and raising the risks for rescuers in times of disaster in a country prone to earthquakes and tsunamis.

The problem of too many homes

Akiya are often passed down through generations. But with Japan’s plummeting fertility rate, many are left with no heir to pass to, or are inherited by younger generations who have moved to the cities and see little value in returning to rural areas, experts told CNN.

Some houses are also left in administrative limbo because local authorities don’t know who the owners are due to poor record-keeping, they said.

That makes it difficult for the government to rejuvenate fast-aging rural communities, hampering efforts to attract younger people interested in an alternative lifestyle or investors eyeing a bargain.

Under Japan’s tax policies, some owners often find it cheaper to retain the home than to demolish it for redevelopment.

And even if owners want to sell, they may have trouble finding buyers, said Hall, from Kanda University.

“Many of these houses are cut off from access to public transport, health care and even convenience stores,” he said.

Trending videos showing people – mainly foreigners – scooping up cheap Japanese houses and turning them into stylish guesthouses and cafes have garnered many followers on social media in recent years, but Hall warned it’s not as easy as it seems.

“The truth is most of these homes are not going to be sold to foreigners, or that the amount of administrative work and the rules behind it [are] not something easy for somebody who doesn’t speak Japanese and read Japanese very well,” he said.

“They’re not going to be able to get these houses for cheap.”

Too few people

Japan’s population has been in decline for several years – at the last count in 2022, the population had shrunk by more than 800,000 since the previous year, to 125.4 million.

In 2023, the number of new births fell for the eighth consecutive year, reaching a record low, according to official data.

Japan’s birth rate has hovered around 1.3 for years, far from the 2.1 needed to maintain a stable population, and just last week Japan’s Ministry of Internal Affairs and Communications said the number of children under age 15 had dropped for the 43rd straight year to a record low of around 14 million, as of April 1.

So, all that means the problem of too many homes and too few people looks set to continue for some time.

Yuki Akiyama, a professor from the faculty of architecture and urban design at Tokyo City University, said vacant houses have caused issues in the past, for example, after the 7.5 magnitude earthquake that hit the Noto Peninsula in the central prefecture of Ishikawa in January.

The area where the quake struck was fraught with akiya, he said, and they posed both a danger to residents during the disaster and challenges for post-earthquake reconstruction.

“When an earthquake or a tsunami occurs, there is a possibility that vacant houses will block evacuation routes as they break down and get destroyed,” he said.

After the earthquake, authorities struggled to decide which damaged properties they could clean up because of unclear ownership, presenting “an obstacle for reconstruction,” said Akiyama.

In other rural areas with a high concentration of vacant houses, akiya have stalled development, the professor said.

With these properties remaining untouched, he said, “The value of the area will be reduced because it is a place where you can’t buy and sell it properly and you can’t do large-scale development.”

“People will think that this place has no value, and the real estate value of the entire area will gradually decrease.”

Akiyama has devised an AI program to predict the areas most vulnerable to akiya, but he stressed the problem isn’t unique to Japan – it has been seen in the US and some countries in Europe.

However, he said Japan’s architectural history and culture made the situation there particularly dire.

Homes in Japan aren’t valued for their longevity, he said, and unlike in the West, people don’t typically see merit in living in historical buildings.

“In Japan, the newer the house, the higher the price it sells for,” he said.

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