Do I need a permit for addition or structural alteration in Douglasville?

Yes. In Georgia, addition or structural alteration generally requires a permit, and Douglasville is no exception.

Additions and any change to load-bearing walls require a permit and reviewed plans in Georgia; removing or altering a bearing wall usually needs engineered details. Additions may trigger energy-code, zoning, and setback review, so confirm the full scope before starting. Douglas County's own permitting office is the Douglas County Building Permits and Inspections, reachable on 770-920-7201 at https://www.douglascountyga.gov/224/Building-Permits-Inspections. 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. Douglas County sits inside the Metropolitan North Georgia Water Planning District, created by the Georgia General Assembly in 2001. Every local government in the District, cities included, has to adopt the District's model post-construction stormwater ordinance or an equivalent one at least as effective, so these rules follow you into any city in the county rather than stopping at the unincorporated line. An addition adds roof area, which counts as impervious surface, and a large one combined with new driveway or patio work can reach the local threshold. In practice the thresholds are aimed at larger development rather than ordinary homeowner work, so most single-family projects sit below them. Cobb County, for example, publishes its trigger as adding more than 5,000 square feet of impervious surface or disturbing more than an acre. Each local government sets its own figures, so check yours before assuming. Where it does apply, the current standard is to retain the first 1.0 inch of rainfall on the site to the maximum extent practicable, which usually means a detention or infiltration feature rather than just grading water to the street. Douglasville charges a $125 plan review fee at intake, basic reviews take 5 to 10 business days, and a resubmittal after denial costs an additional $175. Separate mechanical, electrical, and plumbing permits are required and cannot be issued until the building permit is issued. Zoning verification from Community Development is required before a building permit is issued, and a land disturbance permit must be in hand first where one is required (UDC Sec. 10.09). Buildings of 5,000 square feet or more require plans bearing the wet seal of a Georgia registered architect or engineer.