How Decatur Handles Accessory Structures: A Practical Guide

Decatur maintains 39 local ordinances across all categories, and 4 of those deal specifically with accessory structures. Here is a breakdown of what the city actually requires, what is prohibited, and where Decatur falls on the strict-to-permissive spectrum compared to other cities.

Carport Rules

Decatur regulates carports as accessory structures under the Unified Development Ordinance (UDO), with side and rear setbacks of approximately four feet from property lines in most residential districts, height capped at the lesser of 20 feet or the principal structure, lot coverage subject to district maximums, and a building permit required from the city under the Georgia State Minimum Standard Residential Code.

Key details: Code Reference: Decatur UDO (Part IV), Articles 3 and 7. Side/Rear Setback (Accessory): 4 ft (typical residential). Front Yard: Cannot encroach. Max Height: Lesser of 20 ft or principal structure. Counts Toward Lot Coverage: Yes (impervious area).

Building a carport without a permit, encroaching into a required setback, or pushing the lot over its impervious-coverage cap is a UDO and building code violation enforced by the Decatur Planning Division and Code Enforcement. Penalties include stop-work orders, fines, and required removal or relocation of the structure. Carports added in historic districts without a Certificate of Appropriateness can be ordered removed regardless of permit status.

ADU Rules

ADUs are permitted in Decatur since 2012 in residential zones (R-85, R-60, R-50, RM-18, RM-22, RM-43). Max size is 800 sq ft or 40% of main home, up to 1,200 sq ft absolute maximum. Owner must occupy either the main home or ADU for at least 8 months/year. Two bedrooms maximum. 4-foot setbacks required.

Key details: Permitted Zones: R-85, R-60, R-50, RM-18, RM-22, RM-43. Max Size: 800 sq ft / 40% of main home; max 1,200 sq ft. Max Bedrooms: 2 bedrooms. Owner Occupancy: 8 months/year required. Side/Rear Setbacks: 4 feet minimum.

Operating an ADU without complying with owner-occupancy requirements may result in permit revocation.

Shed Rules

Accessory structures including storage sheds in Decatur are regulated under UDO Article 7 (Site Development) and Article 2 (Residential Use Standards). Sheds must meet setback requirements (typically 5 feet from rear and side lot lines) and are limited in height and footprint relative to the main dwelling.

Key details: Ordinance: UDO Art. 7; Art. 2. Location: Rear or side yard. Typical Setback: 5 feet from rear/side lines. Permit Threshold: Generally required over 144 sq ft. Permit System: communitycore.com.

Building without permit: $200 to $500. Setback violation: forced relocation or removal. HOA fines separate.

Garage Conversions

Garage conversions to living space in Decatur require a building permit and must meet UDO residential standards. Converting to an ADU is permitted subject to ADU rules. Converted garages must comply with building codes for insulation, egress, and fire separation. Loss of required parking spaces must be addressed.

Key details: Permit Required: Yes — building permit. Code Compliance: IRC + UDO standards. ADU Rules Apply: If creating a separate unit. Parking: Must address loss of parking spaces. Contact: Building & Inspections 678-553-6505.

Unpermitted conversion: $500 to $2,000. May require restoration to garage or retroactive permitting.

The Bottom Line

Decatur's accessory structures rules are a mixed bag. Some areas are strict, others are relaxed, and the details matter. The best approach is to check the specific rule that applies to your situation rather than assuming Decatur is broadly strict or permissive.

This guide is based on Decatur's current municipal code. Local rules can and do change, so check the individual ordinance pages for the latest details, penalties, and FAQs.