<p>Stiffening beams act as an effective mechanism to reduce lateral displacements and story drift in coupled shear walls. Despite their advantages, existing analytical models remain restricted to specific configurations, preventing a fully generalized approach. Moreover, they do not account for a newly identified deformation mechanism associated with the local shear of the walls, which plays a crucial role in enhancing the accuracy of classical continuous models. To overcome these limitations, this study presents a Double-Beam Systems Timoshenko model, which consists of the parallel coupling of two Timoshenko beams. New closed-form solution are derived for the static analysis of coupled shear walls—both symmetric and asymmetric—with single or multiple bays, incorporating stiffening beams and subjected to three standard lateral loading conditions. The findings reveal that horizontal deflection can be decomposed into three primary components: bending, shear, and interaction. It is established that the stiffening beam influences only the interaction component, leaving the bending and shear effects unchanged. To enhance the predictive capacity of the continuous model, two static correction factors are introduced. Numerical evaluations demonstrate that classical continuous models are applicable solely to slender walls, which exhibit behavior similar to bending beams. In contrast, their use in non-slender walls leads to significant underestimation of displacements, posing potential structural safety risks. The inclusion of the proposed correction factors extends the model’s applicability to non-slender walls, which align more closely with Timoshenko beam behavior, reducing the maximum error from -60% to ±3%.</p>