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)”. 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)”.