Abstract. Verticality check of prefabricated elements is an essential part of prefabrication construction. Currently, it is mostly carried out by manual methods, which is slow and inefficient. Previous studies have used laser scanning for the quality check but mainly focused on surface defects, flatness, and the dimension of construction elements. Very few studies used laser scanning to evaluate the installation quality of prefabricated elements. Those, who adopted the laser scanning method,

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... pared the as-built with the initial design version of BIM. Such approach requires an accurate design version of BIM with tedious manual tasks relying on human skills that involve errors. This on-going study investigates a verticality check method based on laser scanning for assessing the quality of wall panel installations without relying on previous drawings or BIM. The proposed method enables practitioners to confirm the quality of the wall panel installation and its vertical deviations based on the processed point cloud data. The region growing segmentation and random sample consensus are used to process the acquired data for computing the deviations. This method is validated in a real high-rise prefabrication residential building. Our method took about 9 min/100 m2, versus the conventional method, which took 31 min/100 m2. The experiments indicate that the proposed method is significantly more time-efficient compared to the conventional manual method. The contribution of this study includes suggesting suitable parameters for measuring the vertical dimensions of prefabricated wall panels and deviations that can be replicated in high-rise prefabricated residential projects.