Cobb County, GA Building Setbacks & Zoning: Structure Height Limits (2026)
Key Facts
- Max height, R-20 and most single-family zones
- 35 feet
- Small accessory structure (up to 144 sq ft)
- 15 feet, 5-ft property line setback
- Larger accessory structure (over 650 sq ft)
- 35 feet, 100-ft property line setback
- First zoning violation fine
- $100 to $1,000, up to 60 days jail
- Variance reapplication bar after denial
- 12 months on the same property
- Scope
- Unincorporated Cobb County only
Summary
In unincorporated Cobb County, principal residential structures are capped at 35 feet under the zoning code's single-family district rules. Height runs from the mean ground elevation at the front of the house to the mean level of the highest roof point. Accessory buildings top out separately at 15 or 35 feet depending on size. Marietta, Smyrna, Kennesaw, Acworth, Powder Springs and Austell set their own limits.
(7)Building and structure requirements. Maximum building height is 35 feet. ... (13)Accessory buildings, structures, uses and decks.a.Size and setback limitations: Any accessory building, structure, use and deck up to 144 total gross square feet must be located at least five feet off the property line and limited to 15 feet in height subject to the development conditions list below (except for 15-foot height restriction). Any accessory building, structure, use and deck over 144 total gross square feet and up to 650 total gross square feet shall be limited to the building setbacks of the lot it is located on and is subject to the development conditions below. Any accessory building, structure, use and deck over 650 total gross square feet must be at least 100 feet from any property line and is subject to the development conditions below.b.Accessory buildings, structures, uses and decks shall be subject to the following development conditions:1.Maximum height is two stories or 35 feet.
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: Code of Ordinances: Supplement 53).
Full Breakdown
" The same 35-foot ceiling for the principal structure runs across the county's other single-family zones, including R-80, RR, R-40, R-30, R-15, R-12, and the RD duplex and RA-4/RA-6 attached-detached districts, so a homeowner anywhere in unincorporated Cobb's low-density residential tiers is building to the same number. Multifamily and commercial districts allow more: the RM-8, RM-12 and RM-16 apartment districts cap at 40 feet, and some office and commercial districts run 50 to 75 feet. Section 134-1 defines how the county measures a residential building's height: the vertical distance from the mean ground elevation at the front of the structure to the mean level of the highest point of the roof, with a note flagging section 18-27(e) of the building code for additional height-related permitting requirements.
Accessory structures get a separate, smaller allowance under section 134-197(13)a and b: any accessory building, deck or structure up to 144 total gross square feet must sit at least five feet off the property line and is capped at 15 feet, while larger accessory structures over 650 square feet must sit at least 100 feet from any property line. Once an accessory structure follows the lot's normal building setbacks, its development conditions cap it at two stories or 35 feet, the same ceiling as the house itself.
A homeowner who needs to exceed the 35-foot cap applies for a variance under section 134-34: a notarized application, a county-set fee, and a current boundary survey and plot plan from a registered surveyor or engineer go to the zoning division, with public notice posted before a hearing at the board of zoning appeals. A rejected variance can't be resubmitted for the same property for 12 months. This limit governs unincorporated Cobb only; Marietta, Smyrna, Kennesaw, Acworth, Powder Springs and Austell each set their own height limits under separate municipal codes.
Violations & Fines
Building without a permit or exceeding the 35-foot cap is enforced under section 134-2: a citation to Cobb County Magistrate Court under O.C.G.A. 36-1-20, with a first offense fined $100 to $1,000 and up to 60 days in jail within any 12-month period. A second violation runs $300 to $1,000, a third $600 to $1,000, and a fourth or later violation carries a flat $1,000 fine. The code anticipates the minimum fine applying only where the violation was substantially cured or abated before conviction; any condition on a variance carries the same force of law and the same penalty schedule if violated.
Frequently Asked Questions
How tall can I build a house in unincorporated Cobb County?
Does the 35-foot limit apply inside Marietta or Smyrna?
What is the height limit for a detached garage or pool house?
Can I get a variance to build higher than 35 feet?
Sources & Official References
Other rules in Cobb County
Compare Cobb County to another location·View the Georgia building setbacks & zoning overview
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