St. Tammany Parish, LA Building Setbacks & Zoning: Lot Coverage Limits (2026)

Exhibit 400-2, printed under UDC Sec. 400-2.1, sets a maximum lot coverage percentage for every residential zoning district in the unincorporated parish. The E Estate Residential, R-1 and R-2 Rural Residential, TF Two-Family Residential, and M-L, M-M, and M-H Multi-Family Residential districts all cap coverage at 50 percent of total lot area. The L-1 and L-2 Large Lot Residential districts and the S-1 and S-2 Suburban Residential districts allow more, up to 60 percent. Lot coverage under the parish's definitions counts the footprint of the principal building or buildings together with any accessory buildings, so a house, detached garage, and shed are all measured against the same lot-area percentage.

The coverage cap works alongside the exhibit's yard setbacks rather than instead of them: the E, R-1, and R-2 districts also carry a 50-foot front yard, 15-foot side yard, and 25-foot rear yard, while the more compact TF and multi-family districts drop those setbacks to 25 feet on the front and 7.5 to 10 feet on the sides. A property owner who maxes out the setbacks can still be capped by the coverage percentage if the buildable envelope would otherwise allow more roof area than the district permits.

Coverage runs lower in the Rural Overlay District layered over parts of the parish's agricultural areas. Under Sec. 400-7.F.3.g, a lot within the RO Overlay is capped at 25 percent lot coverage for all principal and accessory buildings, a tighter number than any base residential district, reflecting the overlay's stated preference for keeping land in agricultural or forested use rather than built upon.