Structural safety assessment of buildings in Korea

Four categories of buildings defined in Article 8 of the Enforcement Decree of Korea's Building Management Act are subject to periodic inspection: buildings containing multi-use business premises designated by local ordinance, buildings with a total floor area of 3,000 m² or more to which Korea's Act on Ownership and Management of Condominium Buildings applies, multi-use buildings under the Enforcement Decree of the Building Act, and special-structure buildings among quasi-multi-use buildings. If the periodic inspection finds that safety needs to be secured, the manager must have a safety diagnosis that investigates the causes of defects and proposes repair and reinforcement methods, and the structural safety assessment is that investigation. Sources: Enforcement Decree of Korea's Building Management Act, Article 8 (Buildings subject to periodic inspection, etc.) — https://www.law.go.kr/LSW/lsSideInfoP.do?lsiSeq=289799&joNo=0008&joBrNo=00&docCls=jo&urlMode=lsScJoRltInfoR Korea's Building Management Act, Article 16 (Implementation of safety diagnosis) — https://www.law.go.kr/LSW/lsSideInfoP.do?lsiSeq=266691&joNo=0016&joBrNo=00&docCls=jo&urlMode=lsScJoRltInfoR

It refers to multi-use buildings under Article 2, subparagraph 17 of the Enforcement Decree of Korea's Building Act, and a building qualifies if it meets either of two conditions. One is a building in which the combined floor area used for cultural and assembly facilities (excluding zoos and botanical gardens), religious facilities, retail facilities, passenger transport facilities, general hospitals or tourist accommodation is 5,000 m² or more; the other is a building with 16 or more stories regardless of use. Whether a building is subject to periodic inspection can first be estimated from the number of stories and the floor area by use recorded in the building register. Sources: Enforcement Decree of Korea's Building Act, Article 2 (Definitions) — https://www.law.go.kr/LSW/lsSideInfoP.do?lsiSeq=288849&joNo=0002&joBrNo=00&docCls=jo&urlMode=lsScJoRltInfoR Enforcement Decree of Korea's Building Management Act, Article 8 (Buildings subject to periodic inspection, etc.) — https://www.law.go.kr/LSW/lsSideInfoP.do?lsiSeq=289799&joNo=0008&joBrNo=00&docCls=jo&urlMode=lsScJoRltInfoR

If the combined floor area for the relevant uses is under 5,000 m², the building is not a multi-use building and is not subject to periodic inspection on that criterion. This is because a multi-use building is judged by adding up the floor area used for the specified uses, such as cultural and assembly facilities and retail facilities, not the total floor area of the whole building. Even so, a building with 16 or more stories is a multi-use building regardless of use, and a building with a total floor area of 3,000 m² or more under the Condominium Buildings Act or a building with multi-use business premises designated by ordinance is subject under the other criteria of Article 8 of the Enforcement Decree. Sources: Enforcement Decree of Korea's Building Act, Article 2 (Definitions) — https://www.law.go.kr/LSW/lsSideInfoP.do?lsiSeq=288849&joNo=0002&joBrNo=00&docCls=jo&urlMode=lsScJoRltInfoR Enforcement Decree of Korea's Building Management Act, Article 8 (Buildings subject to periodic inspection, etc.) — https://www.law.go.kr/LSW/lsSideInfoP.do?lsiSeq=289799&joNo=0008&joBrNo=00&docCls=jo&urlMode=lsScJoRltInfoR

Schools under Korea's School Safety Act, multi-family housing subject to mandatory management under the Multi-Family Housing Management Act, and large and quasi-large stores under Korea's Distribution Industry Development Act are excluded from periodic inspection under the Building Management Act. Multi-family housing that has undergone safety management for small multi-family housing within 3 years of the periodic inspection deadline is also excluded. The exclusion applies only to periodic inspection under this Act, so a building showing structural abnormalities such as cracks or deflection can have its condition checked by a structural safety assessment regardless of any inspection obligation. Sources: Enforcement Decree of Korea's Building Management Act, Article 8 (Buildings subject to periodic inspection, etc.) — https://www.law.go.kr/LSW/lsSideInfoP.do?lsiSeq=289799&joNo=0008&joBrNo=00&docCls=jo&urlMode=lsScJoRltInfoR

Yes, it is excluded, but with a time condition. Article 8 of the Enforcement Decree of the Building Management Act excludes only multi-family housing that has undergone safety management for small multi-family housing under Article 34, subparagraph 2 of the Multi-Family Housing Management Act within 3 years from the date the periodic inspection is due, so one round of safety management does not mean permanent exclusion. If more than 3 years separate the safety management date and the next periodic inspection deadline, the periodic inspection must be carried out that round. Sources: Enforcement Decree of Korea's Building Management Act, Article 8 (Buildings subject to periodic inspection, etc.) — https://www.law.go.kr/LSW/lsSideInfoP.do?lsiSeq=289799&joNo=0008&joBrNo=00&docCls=jo&urlMode=lsScJoRltInfoR

HomeCheck's structural safety assessment is carried out with the direct participation of a Professional Engineer in building structures (Korea's national qualification) in three stages: site survey, structural safety review, and comprehensive evaluation with repair and reinforcement proposals. First, the design documents are checked against the actual building, and equipment is used to survey the rebar arrangement, member dimensions and section sizes. The results are entered into mechanical calculations and structural analysis software to review load-bearing capacity, and where capacity is insufficient, repair and reinforcement proposals are presented.

The scope is decided by the purpose of the assessment, the condition of the building and whether drawings survive. If you tell us the phenomena you are concerned about, such as cracks, deflection, fire or settlement, when you first noticed them, and whether you plan an extension or change of use, we decide together at consultation which floors and members to survey and how far to take material testing and structural analysis. Once the scope is set, the items to be included in the structural safety assessment report and the recipient are confirmed in the same meeting.

Yes. A structural safety assessment is possible without drawings. The dimensions of columns, beams, walls and slabs are measured directly on site, and rebar detection equipment is used to confirm the reinforcement, producing structural information to use in place of drawings. The building register and the history of extensions and repairs are also reviewed, and for parts that could not be fully confirmed, the report states the assumptions used in the review.

No. Finishes should not be repaired before confirming how much the frame was damaged by heat. Concrete loses strength under high heat, and exposed rebar or member deflection can occur; refinishing the surface hides this damage. A structural safety assessment is needed to decide the scope of core sampling and strength testing according to the fire location and extent of damage, and to prepare appropriate repair and reinforcement proposals.

To determine whether the cause is foundation settlement or insufficient member capacity, the assessment measures the actual tilt and deflection. The plumb of columns and walls, floor deflection and crack distribution are recorded and compared with the existing drawings, use history and load changes. If deformation is visibly increasing over a short period, it is safer to restrict access and expedite the assessment.

The actual member dimensions, rebar arrangement, concrete strength and damage locations confirmed in the site survey are entered into the structural analysis model for calculation. Because site-measured values are used instead of drawing values, the load-bearing capacity the building can actually provide now can be assessed. Parts with insufficient survey data are filled in with additional tests or conservative values and reflected in the conclusions of the assessment.

If cracks and deflection in the structural members of a building are spreading, a structural safety assessment is needed. Hairline cracks only on wallpaper or finished surfaces may be a finish problem, but wide gaps crossing main frame members such as columns and beams cannot be assessed by appearance alone. Photographing the crack locations and recording their size by date helps determine the scope of the assessment.

The report includes the purpose and subject of the survey, site survey and material test results, load-bearing capacity review results from structural analysis, and the parts requiring repair and reinforcement with proposed methods. Damage locations are marked on photos and drawings, and areas with reduced capacity are classified by priority. If a specific institution, such as a permitting authority, has set required items, please tell us when commissioning.

If you want to know the cause and safety of cracks, deflection or fire damage that has already occurred in the building, commission a structural safety assessment; if you want to know whether a future change such as an extension or change of use will overload the existing structure, commission a structural review. The structural safety assessment focuses on establishing the current condition through site surveys and tests, while the structural review assesses the adequacy of the change plan from drawings and calculations. If the condition of a building about to be altered is in doubt, the right order is to confirm the current condition with a structural safety assessment first.

Repair and reinforcement design proceeds according to the deficient parts and causes stated in the report. There are various methods, such as enlarging member sections or adding carbon fiber or steel plates, and the choice considers the building's use, construction period and cost. If emergency measures such as use restrictions were also proposed, those measures must be followed first until the reinforcement work is completed.

The cost depends on how widely and how deeply the survey goes, and that scope depends on the building's total floor area, number of stories and structural form, such as reinforced concrete or steel. The workload is determined by whether the whole building or only the damaged floors are surveyed, how many locations are core-sampled for strength tests and rebar detection, and whether the structural analysis covers some members or a full building model. For old buildings without drawings, the process of measuring member dimensions on site to create new structural information is added. Send us photos of the building, the building register and any surviving drawings, and HomeCheck will first define the survey scope and quote according to it.

It is not limited to buildings on a set list; any building can be a candidate when its structural safety is in doubt. Typical cases are old buildings where cracks, deflection or settlement are growing, buildings whose frame has been exposed to fire, and buildings whose safety is in question ahead of an extension, major repair, change of use or remodeling. It may also be required by law: Article 16 of Korea's Building Management Act allows the mayor, county governor or district head to demand a safety diagnosis from the manager when a serious defect has occurred or there is a risk of collapse or overturning, and the manager must comply unless there are special reasons. HomeCheck assesses such buildings through site surveys and structural analysis and organizes the causes of defects and repair and reinforcement proposals in a report. Sources: Korea's Building Management Act, Article 16 (Implementation of safety diagnosis) — https://www.law.go.kr/LSW/lsSideInfoP.do?lsiSeq=266691&joNo=0016&joBrNo=00&docCls=jo&urlMode=lsScJoRltInfoR

A structural safety assessment is not required for every change of use. What matters in a change of use is whether the existing structure can bear the loads of the new use, and this is usually confirmed by a structural review or a structural safety confirmation document. A structural safety assessment is needed in addition when there are cracks, deflection or traces of fire, or when the building is so old that the current concrete strength and rebar condition cannot be relied on. For such buildings, HomeCheck first confirms the actual member dimensions and reinforcement through a site survey and proposes repair and reinforcement for parts with insufficient capacity. Sources: Korea's Building Act, Article 19 (Change of use) — https://www.law.go.kr/LSW/lsSideInfoP.do?lsiSeq=273437&joNo=0019&joBrNo=00&docCls=jo&urlMode=lsScJoRltInfoR

Checking in turn whether the company is a registered institution specializing in safety examinations, the technical staff who take part, its equipment and material testing, and the structure of its reports makes it easier to choose. Under Article 28 of the Special Act on the Safety Control and Maintenance of Establishments, an institution specializing in safety examinations receives a registration document after registering with the provincial governor by meeting the criteria for each field, so you can check the registration document and registered field at consultation. At the quotation stage, also ask whether the engineers in charge take part directly in the site survey and analysis, whether rebar detection and strength tests are done with the company's own equipment, and whether the report includes the survey results, calculation basis and repair and reinforcement proposals together. HomeCheck is a registered institution specializing in safety examinations and a registered structural engineering business in Korea, and a Professional Engineer in building structures (Korea's national qualification) takes part directly in the assessment. Sources: Korea's Special Act on the Safety Control and Maintenance of Establishments, Article 28 (Registration of institutions specializing in safety examinations, etc.) — https://www.law.go.kr/LSW/lsSideInfoP.do?lsiSeq=283765&joNo=0028&joBrNo=00&docCls=jo&urlMode=lsScJoRltInfoR

An in-depth safety diagnosis is a statutory diagnosis that the managing entity of a facility designated under the Special Act on the Safety Control and Maintenance of Establishments must receive, while a structural safety assessment is a diagnosis tailored to its purpose whenever a building's structural safety is in doubt, regardless of such designation. The in-depth safety diagnosis must be carried out periodically by the managing entities of Type 1 facilities and the like, with performer qualifications and timing set by law, and a safety grade is designated according to the results. The structural safety assessment differs in that its survey scope is set according to each building's circumstances, such as cracks, fire or extension plans, while the methods of finding causes and repair and reinforcement proposals through site surveys, material tests and structural analysis are similar for both. If you are unsure whether your building is a Type 1 facility, HomeCheck will first confirm at consultation which assessment is appropriate. Sources: Korea's Special Act on the Safety Control and Maintenance of Establishments, Article 12 (Implementation of in-depth safety diagnosis) — https://www.law.go.kr/LSW/lsSideInfoP.do?lsiSeq=283765&joNo=0012&joBrNo=00&docCls=jo&urlMode=lsScJoRltInfoR Korea's Special Act on the Safety Control and Maintenance of Establishments, Article 16 (Designation of facility safety grades, etc.) — https://www.law.go.kr/LSW/lsSideInfoP.do?lsiSeq=283765&joNo=0016&joBrNo=00&docCls=jo&urlMode=lsScJoRltInfoR

The grade is determined after the results of the site survey, material tests and structural analysis are combined to judge the condition of the building. For facilities under the Special Act, Table 8 of the Enforcement Decree divides grades into A (excellent) with no problems, B (good) with minor defects in secondary members, C (fair) with no effect on overall safety but requiring repair, D (deficient) requiring urgent repair and reinforcement, and E (poor) requiring immediate prohibition of use; a structural safety assessment of an ordinary building may also indicate a grade with reference to these criteria. When checking the grade, also look in the report at which members caused that grade and at the recommended measures. If the grade is low or a problem with load-bearing capacity is confirmed, HomeCheck proposes repair and reinforcement. Sources: Enforcement Decree of Korea's Special Act on the Safety Control and Maintenance of Establishments, Table 8 (Safety grade criteria for facilities) — https://www.law.go.kr/LSW/lsBylInfoP.do?bylSeq=18451835&lsiSeq=289677&efYd=20260915&directYn=Y