The massive environmental impacts of the construction industry due to its resource dependency and consumption, emissions, and waste generation cannot be neglected. Implementing the circular economy concepts is recognised as the main solution to the transition of this industry to a more sustainable one. While timber is considered as one of the sustainable construction materials, increased use and demand for timber lead to increased volumes of wood processing residues. In this study, state-of-the-art structural flooring elements that are made of a combination of industrial wood residues in the form of ungraded offcuts and graded timber are investigated. The flooring systems are designed for easier disassembly and circular use in the future. Uncertainties exist regarding these elements’ mechanical properties and expected service life. This research investigated the impact of using industrial wood residues on the long-term service life of these developed systems. Regression models were used to predict the flooring systems’ creep factor and deflection values at long periods in their future life cycles. The results of the long-term bending test are presented to ensure decisions on the long-term and extended service life of state-of-the-art flooring elements. The results highlight the possibility of defining new end-of-life scenarios for both industrial wood residues and flooring systems, ensuring the long-term quality of these systems based on long-term service life assessments. This can increase the utilization rate of industrial wood residues in high-quality structural systems, leading to an increase in the carbon storage time and contributing to the existing net-zero emissions strategies