As ultra-high-rise designs exceeding 50 stories proliferate across Seoul's redevelopment and reconstruction sites, controversy has emerged over the safety and feasibility of projects proposing unusually short construction timelines. Experts point out that construction duration alone should not be used to assess safety, and that construction methods, investment costs, and quality management must also be considered.
According to the industry on Monday, competition to build ultra-high-rises has intensified this year at major redevelopment sites in Seoul. In Apgujeong-dong, Gangnam-gu, one of the largest reconstruction areas, design plans exceeding 60 stories are being pursued across Districts 2, 3, 4, and 5.
DL E&C has signaled its intent to win the Apgujeong District 5 reconstruction project (up to 68 stories) by proposing a construction period of 57 months, shorter than the industry norm. The timeline drew attention as most recent ultra-high-rise redevelopment projects along the Han River have been proposed at 60 months or more. The construction period for the Seongsu District 1 project (64 stories) was proposed at 63 months, while Apgujeong District 4 (67 stories) was proposed at 68 months. DL E&C said that shortening the construction period can reduce financing costs for union members and that it possesses know-how in shortening project timelines at other sites.
Recently completed high-rise residential complexes show that the number of stories and construction period are generally proportional. Brighten Yeouido (49 stories), completed in August 2023, took 49 months from groundbreaking to completion, while Cheongnyangni Station Hanyang Sujain Graciel (59 stories), completed in June of the same year, took 58 months. Cheongnyangni Station Lotte Castle SKY-L65 (65 stories) took 59 months, and Yongsan Central Park (43 stories), completed in August 2020, took 43 months.
Ultra-high-rise buildings exceeding 50 stories in particular are subject to stricter standards than ordinary apartment complexes, which can extend construction periods. Under current law, buildings of 50 stories or more or 200 meters or taller are classified as ultra-high-rise buildings and must meet separate safety standards, including the installation of refuge safety zones at designated floor intervals.
Experts say the complexity of ultra-high-rise construction must be considered, but that judging safety based solely on construction duration is unreasonable. "Construction projects have a structure in which construction period, construction cost, and quality interact with each other," said Choi Soo-young, a research fellow at the Construction & Economy Research Institute of Korea. "Shortening the period may require additional costs and resources, and conversely, if the period is shortened while costs remain the same, it could affect quality and safety." Ahn Hyung-joon, research director at the Council on Tall Buildings and Urban Habitat Korea, said, "Construction period and building safety are separate issues. When assessing safety, variables including construction methods and materials must be considered." Chae Ji-yong, a senior researcher at the Korea Institute of Civil Engineering and Building Technology, said, "Design data and construction experience for ultra-high-rise buildings have accumulated, and process management and construction technologies have been largely optimized. Recently, early-strength concrete technology, modular construction, and top-down methods have advanced, improving timeline efficiency."
