Louisiana State Construction Code Governs ADUs

La. R.S. 40:1730.28 requires every parish and municipality to enforce the LSUCC, which incorporates the International Residential Code for one- and two-family dwellings. ADUs, whether attached or detached, must meet IRC requirements for egress, fire separation, energy conservation, and elevation in flood zones under La. R.S. 38:84 and FEMA-mapped areas. The statute prohibits local amendments that lower these construction standards. Zoning, density, owner-occupancy, and short-term rental conditions remain entirely within local authority, so cities like New Orleans and Baton Rouge may still restrict where ADUs are permitted by use district.

Constructing an ADU without LSUCC-compliant permits exposes owners to stop-work orders, civil penalties under local enforcement, and inability to obtain a certificate of occupancy.