Section 301.1/Existing Building Compliance Scope
IEBC 301 establishes when the existing building code applies and the three compliance methods for alterations, repairs, and changes of occupancy.
The IEBC applies to the repair, alteration, change of occupancy, addition, and relocation of existing buildings. Three compliance methods are available: the prescriptive method (Chapters 4-12), the work area method (Chapter 8 of the IBC), and the performance method (Chapter 13). The prescriptive method categorizes work by type (repair, Level 1 alteration, Level 2, Level 3, change of occupancy) and specifies the requirements for each level. Existing elements not being altered are generally permitted to remain as-is unless they create a distinct hazard.
Why this section exists
Applying the full new construction code to every renovation project would make most building modifications financially impractical and would discourage building owners from maintaining and improving their properties. The IEBC provides a proportional approach: minor repairs require minimal upgrades, while major alterations and occupancy changes trigger progressively more comprehensive compliance requirements.
What plan reviewers look for
Plan reviewers first determine the scope of work (repair, alteration level 1/2/3, change of occupancy, addition) and which compliance method the designer is using. They verify that the code analysis correctly classifies the work and identifies which building elements must be brought into compliance. The most common error is misclassifying the work level to avoid triggering accessibility, structural, or fire protection upgrades.
Common violations
Related IEBC requirements
Chapter 5 (Section 503) covers Level 2 alterations. Chapter 7 (Section 706) covers accessibility requirements for alterations. Chapter 10 covers change of occupancy. The IBC applies to new construction and additions.