As the weather warms, Seoul's high-rise buildings are getting a spring cleaning, which means it is a peak season for one of the most dangerous jobs in the country: high-altitude window cleaners.

Suspended by ropes, these workers dangle from the tops of tall buildings to clean their windows and facades, creating a perilous sight for onlookers. However, such high-altitude window cleaning has become a familiar scene in the city where high-rise buildings and apartment complexes dominate the skyline.

“This morning, our apartment complex informed residents via audio announcement that workers will be cleaning the windows and exterior facades starting today, and that those concerned about privacy should keep their windows closed,” said a resident of a 35-story apartment complex in Gwacheon, Gyeonggi Province. “If you’re not informed, it would certainly be very surprising to find someone outside your window.”

As of 2024, Korea's capital city is home to approximately 3,088 apartment complexes and over 500 buildings that are 30 stories or taller – highlighting the scale of demand for such high-altitude window cleaning work.

Exterior facade cleaning is typically recommended once or twice a year, but spring is the most common season for it, as it helps remove dust accumulated over the winter months.

According to local services marketplace Soomgo, which directly connects skilled workers with tasks, building exterior cleaning services were offered at 601,000 won ($409) “per service.” It wasn’t clear whether that refers to the labor of one person. Prices can range from 403,000 won to 1 million won, depending on the material of the facade -- such as glass, panels, marble, tile, or brick -- the marketplace app notes.

One company providing building exterior cleaning services told The Korea Herald that the price varies significantly depending on the difficulty of the task and can only be estimated after a site visit.

For high-rise buildings, the cost tends to be even higher, as the job becomes significantly more complex and dangerous.

Seo Seung-ho, a professional cleaner who appeared on tvN talk show “You Quiz on the Block” last year, said it took about six months to clean the exterior of Lotte Tower — the tallest building in South Korea. For skyscrapers like this, water cannot be used due to the risk of it falling onto pedestrians below. Instead, workers use diatomaceous earth, a fine powder made from fossilized algae.

Despite steady demand, safety remains a pressing concern in the industry. Common causes of accidents include the failure to wear safety harnesses, worn-out ropes, faulty safety equipment and poor management.

In August 2023, a man in his 60s died after falling from the 10th floor while cleaning a glass wall in Seoul’s Geumcheon-gu. The authorities found that he had not secured his safety rope to the suspended platform. In 2022, another worker in his 60s fell to his death while cleaning a building in Yeongdeungpo-gu after his rope reportedly came loose. A similar accident occurred in 2019, also in Yeongdeungpo-gu, when a man in his 50s died while working alone on a hospital building.