Paper Title
Quality Perception of Main Constructors and Sub-Contractors on The Internal Wall Inspection: Case of High-Rise Residential Buildings in Thailand

Abstract
Real estate investment, one of the key economic drivers in Thailand, is likely to increase continuously, especially concerning high-rise residential building projects in major cities. According to the literature review, problems on the quality inspection of architectural works cause reworking and cost overrun. Internal wall construction is selected for this study to investigate the possible conflicts and limitations arising during the quality inspection process of high-rise building construction projects. According to the regulations of construction-related organizations in Thailand, the specifications of internal wall quality inspection are subjective, and mostly involve the perception and judgment of inspectors. Main contractors and sub-contractors, who experience high-rise residential building constructions were selected for this qualitative research. Six purposive interviewees, with the collected data analyzed using content analysis. The findings indicate that main contractorsand sub-contractors agree that the quality of internal walls in high-rise buildings are measured by the discretion, knowledge, ability, experience, expertise of each inspector. The quality of work assessment is not consistent between deliverers (Sub-contractors) and inspectors (Main contractors). Internal wall quality emphasizes flatness, alignment and evenness, angle, cracks, and range. However, there is a lack of clear prescription standards for work such as tolerance acceptance. Keywords - Real estate, Residential project, High-rise building, internal wall, Quality inspection process.