Currently, although various manufacturers offer highly mature commercial construction robots, these machines cannot be directly applied to construction sites. Dedicated supporting systems are required to calibrate operational parameters and optimize material compositions. Through repeated testing and calibration, the robots can then be deployed for on-site construction. By adopting a human–robot collaborative approach, these systems can effectively substitute traditional manual construction methods. Therefore this study investigates the feasibility of implementing a fully commercialized painting robot for on-site automated construction, along with the optimization of operational parameters and paint material formulations. Field tests were conducted in sample houses on construction sites managed by a general contractor. The results indicate that the painting robot maintains stable construction quality but suffers from low operational efficiency and excessive material consumption. To enhance overall performance, this study proposes a human–robot collaborative workflow integrating the experiential expertise of skilled craftsmen to refine paint mixture designs. The findings provide critical optimization parameters for establishing practical support measures for construction automation, contributing to improved productivity and reduced dependence on manual labor.