Baton Rouge, LA Accessory Structures: ADU Permits (2026)

The City of Baton Rouge and East Baton Rouge Parish operate as a consolidated City-Parish government under the Plan of Government. Land use is regulated through the Unified Development Code (UDC), administered by the Department of Development (formerly Planning Commission) and codified through the Code of Ordinances on Municode. The UDC permits accessory living quarters (the local term for ADUs) in A1, A2, A2.1, A2.2, A3, A3.1, A3.2, A4, and A4.1 single-family residential zones, generally as accessory uses subject to: a single accessory living quarters per lot; placement behind the front building line of the principal dwelling; setbacks matching the underlying district (typical rear and side 5-10 feet); maximum height tied to the accessory structure cap for the zone (often 25 feet or one story below the principal dwelling, whichever is less); and lot-size minimums. Permits required: zoning compliance review through the Department of Development; building permit through Permits and Inspections under the 2021 Louisiana State Uniform Construction Code (LSUCC), which adopts the 2021 IRC with Louisiana amendments; and trade permits for electrical, mechanical, and plumbing. Applications run through the EBR e-Permits portal. Properties in the Beauregard Town, Spanish Town, or Garden District local historic districts require Historic Preservation Commission review for exterior alterations visible from the public way. Much of Baton Rouge sits in FEMA flood zones along the Mississippi River, Bayou Manchac, and Ward Creek — A and AE zone construction requires elevation per LSUCC Appendix G to Base Flood Elevation plus the local freeboard.