Garage Conversions: Alpharetta vs Atlanta
How do garage conversions rules compare between Alpharetta, GA and Atlanta, GA?
Alpharetta and Atlanta have similar restriction levels.
Alpharetta, GA
Fulton County
Converting a garage to habitable space in Fulton County requires a building permit, plan review, electrical/plumbing/mechanical permits, and compliance with IRC habitable-space requirements. Off-street parking must be replaced.
View full Alpharetta rules →Atlanta, GA
Fulton County
Atlanta currently prohibits attached ADUs, so a garage conversion into a separate dwelling is not allowed by-right; converting a garage to additional living space for the primary dwelling requires a building permit from the Office of Buildings under the Georgia State Minimum Standard Residential Code (2018 IRC with GA amendments).
View full Atlanta rules →Key Facts Comparison
| Fact | Alpharetta | Atlanta |
|---|---|---|
| IRC ceiling height | 7 ft min | - |
| Parking | Must be replaced | - |
| ADU rules if separate | 750 sq ft max | - |
| Attached ADU Status | - | Currently prohibited (Part 16) |
| Allowed Districts (detached only) | - | R-4, R-4A, R-5 |
| Permit | - | Building permit, Office of Buildings |
| Building Code | - | GA State Min. Std. (2018 IRC) - 2024 IRC eff. 1/1/2026 |
| Trade Permits | - | Separate plumbing/electrical/HVAC required |
| Pending Reform | - | ADU code amendment proposal (DCP) |
Highlighted rows indicate differences between cities.
Alpharetta FAQ
Can I convert without a permit?
No — it triggers structural, electrical, and mechanical permits.
Do I lose required parking?
You must replace it elsewhere on-site.
Atlanta FAQ
Can I convert my garage into a separate apartment or ADU in Atlanta?
Not under current zoning. Atlanta's Part 16 code currently allows ADUs only as detached structures in R-4, R-4A, and R-5 districts. A Department of City Planning proposal would allow attached ADUs up to 50% of the main house or 1,000 sq ft, but that change has not yet been adopted.
Do I need a permit to turn my garage into a den or bedroom for my own household?
Yes. Any conversion of garage space into conditioned living area for the existing dwelling requires a building permit from the Atlanta Office of Buildings, plus separate trade permits for plumbing, electrical, and HVAC work.
What building code applies to a garage conversion in Atlanta?
The Georgia State Minimum Standard One and Two Family Dwelling Code, currently the 2018 IRC with Georgia amendments. Permits submitted on or after January 1, 2026 will be reviewed under the 2024 IRC with Georgia amendments.
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