<p>The construction industry is now more proactive on issues relating to environmental sustainability, triggering further research into the development of greener and more effective materials. As a result, there is now increased demand for sustainable products that protect and preserve the environment while retaining the needed performance levels. Due to their low weight-to-strength ratios, natural fibre composites from bio-based resins and renewable fibres represent a promising alternative. This study focuses on evaluating the mechanical properties of flax fibre-reinforced composites through experimental testing. Several tests were conducted to assess the material’s strength, stiffness, and failure modes. Special focus was placed on interlaminar shear strength, as delamination failures are critical in layered composites. The research adds on the understanding of natural fibre composites and provides evidence on the viability of natural fibre composites to be used in construction in support of sustainable development.</p>