How the NBC 2020 is laid out across two volumes
You cannot tab a book you cannot picture, and the NBC 2020 has a shape that trips people up: three Divisions spread across two physical volumes, with the same page numbers repeated in each Division.
Volume 1: Division A, Division B Parts 1 to 8, the appendices and Division C
Division A holds Part 1 (compliance and application), Part 2 (objectives) and Part 3 (functional statements). Division B, the acceptable solutions, runs Part 1 General, Part 2 Farm Buildings, Part 3 Fire Protection, Occupant Safety and Accessibility, Part 4 Structural Design, Part 5 Environmental Separation, Part 6 Heating, Ventilating and Air-conditioning, Part 7 Plumbing Services and Part 8 Safety Measures at Construction and Demolition Sites. Then come Appendix C (climatic and seismic data) and Appendix D (fire-performance ratings), followed by Division C, the administrative provisions, and the index. There are no Parts 10, 11 or 12; those belong to the Ontario code.
Volume 2: Division B Part 9 only
The second volume is Part 9, Housing and Small Buildings, with its own index. It is the whole small-buildings path: structure, envelope, fire, egress, plumbing, ventilation and the 9.36 energy provisions. Objective 5.3 gives it roughly a quarter of the NBC material on the exam, so it gets its own flags and its own colours rather than an afterthought at the end of the Part 3 set.
Notes, folios and the page-number trap
The Appendix A explanatory notes are not in a separate volume. They sit at the end of each Part, so the note explaining occupancy classification examples, A-3.1.2.1.(1), is on page 3-226, well past the last article of Part 3. Because Division A, Division B and Division C each number their pages from 1-1, the folio 3-1 exists three times: Division A Part 3 (functional statements), Division B Part 3 (fire protection) and the NECB's own Division A. Write the Division on the flag when a tab points into Division A or C.
The Part 3 versus Part 9 decision
Every Section 2 scenario starts with one question: which path? Division A Article 1.3.3.3 puts a building in Part 9 only when all three conditions hold: three storeys or less in building height, a building area of 600 square metres or less, and a major occupancy of Group C residential, Group D business, Group E mercantile, Group F Divisions 2 or 3 industrial, or Group B Division 4 home-type care. Fail any one and Article 1.3.3.2 sends the building to Parts 3 to 6. Article 1.3.3.4 adds the firewall rule: portions divided by a firewall count as separate buildings. Tab those two pages (1-2 and 1-3) first, because the Part 3 versus Part 9 guide is the most common place to lose a mark before you have opened the technical Parts.