Information on structural irregularities can be found in the Commentary entitled “Design for Seismic Effects” in the “Structural Commentaries (User’s Guide – NBC 2020: Part 4 of Division B)”. Uncoupled concrete and masonry shear walls where a large fraction of the overturning resistance is provided by axial compression, rather than through yielding of the longitudinal reinforcement, are less susceptible to amplified displacements due to gravity-induced lateral demands because the axial loads have a self-centering effect on the shear walls. Walls that are stronger than the foundation and other systems such as coupled walls, braced frames and moment frames are more susceptible to amplified displacements due to gravity-induced lateral demands. A lower limit on α is thus specified for such systems. Further information on the impacts of gravity-induced lateral demands on the seismic response of buildings can be found in the Commentary entitled “Design for Seismic Effects” in the “Structural Commentaries (User’s Guide – NBC 2020: Part 4 of Division B)”.