Do I need a permit for screen enclosure or pool cage in Marietta?

Yes. In Georgia, screen enclosure or pool cage generally requires a permit, and Marietta is no exception.

A screen room or patio cover attached to the house is a structure that generally needs a permit and setback review; a freestanding, non-roofed screen may be treated more lightly by some jurisdictions. Adding a roof cover can trigger structural, drainage, and (if enclosed) electrical review. Cobb County's own permitting office is the Cobb County Development and Inspections, reachable on 770-528-1000 at https://www.cobbcounty.gov/community-development/building-development/permitting. Its online permit portal is https://cobbca.cobbcounty.gov/CitizenAccess/default.aspx. It issues permits for the unincorporated county. If your city does not run its own building department, and many smaller Georgia municipalities do not, this is the office that will handle the job. An attached enclosure is a structural addition, so expect a plan review and a footing and attachment inspection. Marietta requires a permit to construct or enlarge a structure, and its permit FAQ lists decks, whether new, repaired, or replaced, as an example of work needing one. An enclosure attached to the house is treated as part of the principal building for setbacks, while a freestanding one is an accessory structure held to the district's side and rear setbacks, 10 feet in R-4 under 708.04(F). City of Marietta addresses (Cobb tax district 4, MARIETTA) are permitted and inspected by the City of Marietta Building Inspections office at 205 Lawrence Street, 770-794-5659. Addresses in tax district 9, UNINCORPORATED, go to Cobb County instead.