Effects of Lateral Earth Pressure, H, in Design Calculations
For common building structures below ground level, such as walls, columns and frames, 1.5 H is added to load combinations 2 to 4. For cantilever retaining wall structures, see the Commentary entitled “Limit States Design” in the “Structural Commentaries (User’s Guide – NBC 2020: Part 4 of Division B)”.
Effects of Pre-Stress, P, and Imposed Deformation, T, in Design Calculations
For structures and building envelopes designed in accordance with the requirements specified in the standards listed in Section 4.3., with the exception of Clauses 8 and 18 of CSA A23.3, P and T need not be included in the load combinations of Table 4.1.3.2.-A. For structures not within the scope of the standards listed in Section 4.3., including building envelopes, P and T must be taken into account in the design calculations. For recommended load combinations including T, see the Commentary entitled “Limit States Design” in the “Structural Commentaries (User’s Guide – NBC 2020: Part 4 of Division B)”.