[Exclusive] LH “Quality Master” with an Eagle Eye Catches 2.8mm Steel Plate Instead of 3.2mm... Major Defects Down 68% in 3 Years [LH Private Participation Apartment]

② LH Quality Masters Who Caught On-Site Defects
Filling Gaps Missed by Supervisors and Contractors
"Falsified Steel Plate Thickness, Improper Window Installation"
Rising Reliance on Foreign Labor
Quality Master System Faces Phase-Out D

Experts have pointed out that in order for the LH private participation project to move beyond housing quality controversies, it is necessary to take proactive measures, such as reviving the "LH Quality Master System."

This system was introduced with the intention of deploying skilled workers with over 20 years of experience early in the construction process to prevent defects and improve quality. However, it was never legislated into law.

According to LH on October 10, the number of major defects directly affecting resident safety and daily life decreased by 68%, from 793 cases (0.018 cases per household) in 2021 to 250 cases (0.005 cases per household) last year, thanks to the master system.

Construction site of LH apartment in Gyeonggi. (Far left) Sheet material used for waterproofing the exterior wall of the underground parking lot is left torn and crumpled. (Top right) After waterproofing the exterior wall, the edge finishing was omitted, causing the sheet to lift and rainwater to accumulate inside. When it rained, water seeped down the exterior wall and accumulated inside the sheet, damaging the entire waterproofing layer. (Bottom right) After the LH quality master inspected the area, he pointed out that the entire section needed to be removed and repaired, leading to reinstallation. The damaged section was removed, the edge was fixed with a stainless steel plate, and a new sheet was attached. A blue protective plate was added to prevent damage to the waterproofing layer when backfilling the soil.

Steel plate supposed to be 3.2mm, but actually 2.8mm... Quality Masters Catch Shortcuts at LH Sites

On-site, there have been many cases where quality masters have identified material defects and shortcut construction methods that even supervisors and contractors missed.

At one site, instead of using formwork steel plates with a thickness of at least 3.2mm as ordered by the contractor, a subcontractor secretly installed plates less than 2.8mm thick to cut costs. While the factory presented materials that met the standards, substandard materials were actually brought to the site. LH Master A, a former master at Samsung C&T, said, "When we measured on site, the thickness was significantly below the standard," and added, "If these had been used, it would have caused not only wall deformation during concrete filling, but also a chain of defects affecting insulation and windows." As a result, all of the non-compliant materials were removed from the site.

Shortcuts were also repeated during window installation. In principle, calblock anchors should have been used for deep fixation. However, at another site, bullet-type screws were often used to save time. Although it appeared completed from the outside, the windows could easily fall off. The quality master immediately demanded correction, stating, "This does not meet the standards," and even filed a direct complaint with the contractor's headquarters to resolve the issue.

For insulation installation, the joints were supposed to be reinforced with tape and urethane foam, but this step was skipped. The quality master pointed this out, but the subcontractor delayed taking action. Eventually, the main contractor was instructed to correct the issue. LH Master B, also a former Samsung C&T master, explained, "At Samsung C&T, if anything was missing, we would grind off 15mm and always refill with urethane foam," adding, "But at LH sites, it was done carelessly, just thrown in and left."

The quality master also acted as a mediator between LH and the contractors. An official from a major construction company participating in the private partnership project said, "Among large construction companies, there is a reluctance to collaborate with LH," and explained, "Contractors and LH, as the client, have different interests, which leads to frequent conflicts, and ultimately, contractors have no choice but to comply with LH's demands as the client."

The site manager of a construction company ranked around 40th in construction capability evaluations said, "In private sector projects, we build apartments under our own name, so if customers are dissatisfied, the company handles it directly," and added, "In public projects, residents are not direct customers of the construction company, so cost savings and securing profits become the priority for contractors." He continued, "LH always demands higher quality for the same price, making conflict inevitable. In such cases, the quality master would set standards by saying, 'This level is a defect, this much is acceptable,' which helped resolve disputes." Another site manager from a mid-sized construction company said, "LH and the contractors have different positions, which leads to clashes, but the quality master, although affiliated with LH, played a neutral, intermediary role."

Incheon LH apartment construction site. The electrical conduit and piping embedded inside the bathroom wall are exposed without cement plaster (gap filling). This is a preliminary process that must be completed before waterproofing, but it has not been properly carried out. If water seeps through the wall gaps, it can lead to secondary defects such as leakage, condensation, and electrical short circuits.

The Disappearance of the Quality Masters

The quality master system was intended to be included in the enforcement decree based on the Framework Act on the Construction Industry, but the process has stalled. An LH official said, "This year's program has ended, and there were internal opinions that its role overlapped with that of supervisors," adding, "We plan to reorganize the quality master role into a different system starting next year."

Quality masters are skilled workers who have spent decades specializing in specific processes and directly inspect vulnerable stages on site. This is different from supervisors, who are often focused on administrative procedures and may not catch detailed defects in advance. For this reason, some argue that the system should not be abolished due to concerns about overlapping costs.

Kim Yonghak, President of the Korea Association of Master Construction Technicians, said, "If quality masters are brought in as short-term contractors during the middle of a project, it is difficult for them to fully utilize their expertise," and continued, "A direct employment system, from groundbreaking to completion, must be established for the effectiveness of quality management to be proven with data." He added, "On construction sites, failing to catch faulty work often causes defect repair costs to snowball," and emphasized, "Ultimately, timely quality management is key to reducing construction costs and minimizing damage to residents."