The code that lets existing buildings be repaired, altered and reused safely — without forcing them to meet new-construction requirements.

The 2021 International Existing Building Code (IEBC) governs repair, alteration, addition and change of occupancy in existing and historic buildings. Its purpose is practical: hold the work to an appropriate level of safety while recognising that full compliance with the new-construction provisions of the other I-Codes would make most adaptive reuse impossible. For anyone renovating, converting or restoring existing stock, this is the controlling document.