In Seoul, there are approximately 580 thousand buildings, of which 50.4% are over 30 years old since their approval for use. Legal regulations regarding the safety and maintenance of buildings have been steadily strengthened, meaning that older buildings are likely to have vulnerable performances. However, only 12% of these buildings are subject to mandatory legal management. With implementation of the Building Management Act in 2020, a legal basis was established for local governments to manage small deteriorated buildings defined as buildings over 30 years old that meet certain criteria set by municipal ordinances. A local construction safety center (LCSC) in Seoul metropolitan government conducts safety inspections on 10 thousand buildings each year. In the past five years, approximately 38 thousand buildings have been inspected, representing only 14.6% of small deteriorated buildings in Seoul. Although the LCSC of Seoul has been conducting a structural retrofit support program, it has shown limited results due to requirement for property owners to bear some costs. This study aimed to analyse the current status of safety management support projects for these small deteriorated buildings and to propose ways to enhance their effectiveness.
Legal regulations related to small deteriorated buildings primarily include the Building Management Act and the Building Act. The Building Management Act defines the scope of small deteriorated buildings, while specific building sizes are to be determined by local ordinances. All 24 autonomous districts in Seoul, except for Gangnam-gu, have implemented their own ordinances, showing variations in the scope of small deteriorated buildings. The Building Act stipulates details regarding LCSC (which is responsible for managing small deteriorated buildings) and the dedicated budget from a special account of construction safety. Both Seoul and the 25 autonomous districts have established LCSC. However, only the main office (Seoul metropolitan government) and two districts (Gangdong-gu, Nowon-gu) are organised as independent divisions.
Safety management policies for small deteriorated buildings in Seoul can be mainly divided into 1st and 2nd safety inspections, detailed assessments and structural retrofit support programs. The 1st safety inspection is performed for 15 thousand buildings annually. The LCSC of Seoul has also developed a building safety management information system and utilises its own safety inspection checklist. The 2nd safety inspection is conducted when results of the 1st inspection are poor. An analysis of 50 results of 2nd inspection revealed that a cost of 2nd inspection over ten times more than 1st inspections. Some evaluation criteria were found to be irrelevant. LCSC of Seoul is actively encouraging structural retrofit in vulnerable buildings by reducing the financial burden on property owners.
A survey was conducted among representatives of LCSC in 10 autonomous districts to gather opinions on the safety management policy for small deteriorated buildings. First, to secure the safety of a large number of these buildings, the survey focused on increasing inspection volumes through reallocating budgets for the structural retrofit support program and improving evaluation criteria in the inspection checklist. Most respondents felt that reallocating the budget for the retrofit support program was inappropriate and that current inspection checklist items represented only a minimum standard. Additionally, property owners being uncooperative makes effective safety inspections difficult. Requests for inspections are often related to habitability (e.g., damage on finishes) rather than structural safety. Despite reducing the financial burden on owners, the structural retrofit support program still shows limited results, largely due to the current system requiring support only after costs are paid upfront. There was a significant variability in reports of inspection results according to different experts, leading to substantial burdens for administrative officials. Even with the development of the information system, existing workloads are not resolved.
Measures to improve the safety management policy for small deteriorated buildings are proposed. It is not feasible to conduct comprehensive inspections of all small deteriorated buildings in Seoul under the current system. Therefore, property owners need to use a self-assessment checklist that is easily accessible without expertise and request inspections from LCSC as needed. Furthermore, by using a rapid visual screening method by FEMA, autonomous districts can easily assess safety performances of buildings and prioritise them. The current primary safety inspection in Seoul also needs to be legalised, similar to inspection of actual status of class-iii establishments under the Special Act on the Safety Control and Maintenance of Establishments. Publicity also needs to be strengthened to instill the awareness that property owners must manage their own buildings.
To revitalise the structural retrofit support program, eliminating financial burden on property owners and adopting an upfront payment method for support costs are suggested. However, selection criteria for the program should be sufficiently strengthened to reduce complaints. Furthermore, IoT sensors need to be installed for vulnerable buildings that cannot be reinforced immediately. By installing sensors to measure building tilt and crack width, risks of vulnerable buildings can be detected, ensuring the safety of property owners and nearby residents. Additionally, it is recommended to enhance the connection with the Seumter (national administration for houses and buildings) and propose advanced features to facilitate registration of inspection results. Mandatory training for inspectors by online lectures and improvements to evaluation indicators for the building safety sector in joint assessments by local governments are also suggested to secure work independence.