The rules section. NBC 2020 and NECB 2020. Memorization matters here, and so does knowing where to look it up.
Section 2 is the most cited, most quoted, most look-it-up section of the ExAC. Get fluent with the structure of the codes, not just the content.
The references behind every practice question in Section 2.
National Building Code of Canada
National Energy Code of Canada
Visual guide for small buildings
Advice from people who took the test and remember what tripped them up.
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See how Examitect explains every answer with real book references.
ExAC sitting rules can vary by year. Check the latest CACB ExAC handbook for the current rule. Examitect treats Section 2 as closed-book for practice, since that's the harder default.
NBC takes the larger share, but NECB is growing every cycle. Don't skip energy code. It's the easiest section to underestimate.
NBC 2020. The ExAC has updated to the 2020 edition, and the differences from 2015 matter for several questions.
Most NECB questions test the prescriptive path. Learn the climate zones and the maximum allowed U-values per zone. Calculations are rare, lookups are common.
Each section is a separate test. Many candidates write them out of order.