The current US design codes (American Concrete Institute 318.2-19 and 349) provide limited guidance for the design of reinforced concrete walls in industrial facilities. Unlike building structures, where the walls are slender shear walls, or elevator core structures, in industrial facilities, walls are part of a labyrinthine structural layout consisting of several interconnected walls with low aspect ratios. These walls can be discretized into wall panels, and each panel needs to be designed for eight simultaneous demand types: three membrane forces, three moments, and two out-of-plane shears. This paper presents the Eurocode ‘sandwich’ model approach, which directly accounts for the interaction of the eight demand types acting simultaneously and applies the approach for the design of reinforced concrete wall panels. The paper: (i) explains the background theory leading to the development of the ‘sandwich’ model approach, (ii) presents a design flowchart to facilitate its application, (iii) validates the approach using experimental data and benchmarked inelastic, non-linear analytical models, and (iv) illustrates the use of the approach in real design applications. The results indicate that the Eurocode ‘sandwich’ model approach can be used to design and optimize the steel reinforcement required for reinforced concrete wall panels in industrial facilities.