Atlanta, Georgia | Multiplex Guide
The Atlanta Multiplex Guide: What You Can Build on a Residential Lot in 2026
If you own a house lot in the City of Atlanta, the zoning district on the City's map decides how many homes the lot can hold. In seven of the nine single-family districts the answer is one house. Two more, R-4 and R-4A, also allow one detached accessory dwelling unit (ADU), a small second home behind the main house. The two-family district, R-5, allows a duplex. Three or more homes need a multi-family district such as RG or MR, and for a lot in an R district that means asking City Council to rezone the land.
Atlanta is also rewriting its whole zoning ordinance in a project the City calls ATL Zoning 2.0. The ordinance was referred to the City Council's Zoning Committee on September 8, 2026 and held there on September 14 and September 28, 2026. Until Council adopts it, the 1982 Zoning Ordinance, as amended, is the law. This guide gives the current rules first and labels every draft rule as proposed.
VanPlex is a multiplex company in Vancouver, British Columbia. We do not build, lend or sell property in the United States. We wrote this guide as a reference for Atlanta owners, and every rule on it is linked to the City code, the Council file or the state agency that wrote it.
Atlanta multiplex rules in six facts
- Atlanta's zoning code allows one house per lot in R-1 through R-4B. Only R-4, R-4A and R-5 lots may add a detached accessory dwelling unit (ADU) of up to 750 square feet. Source: Atlanta Zoning Ordinance, Sec. 16-06.004
- R-5 is Atlanta's two-family district. A duplex there needs a 7,500 square foot lot with 50 feet of frontage, and its floor area ratio is capped at 0.60. Source: Atlanta Zoning Ordinance, Secs. 16-07.007 and 16-07.008
- Three or more homes need RG, R-LC, MR or similar zoning. The MR-MU district requires at least 4 and at most 12 homes on a lot, in one building of up to 35 feet. Source: Atlanta Zoning Ordinance, Chapter 35
- Atlanta's zoning rewrite, ATL Zoning 2.0 (ordinance 26-O-1508), was held in the City Council's Zoning Committee on September 14 and September 28, 2026. It has not been adopted. Source: Council file 26-O-1508
- Georgia signed no statewide ADU or lot-size law in 2025 or 2026. Each city and county sets its own rule. Source: Governor's signed legislation, 2026
- The City of Atlanta permitted 78 two-unit buildings and 64 buildings of three or four units in 2025, out of 94 and 98 in the whole metro area. Source: Census Building Permits Survey
Two homes from Sec. 16-06.004 and Sec. 16-07.003. ADU size from the definition in Sec. 16-29.001. MR-MU from Sec. 16-35.011. Permits from the Census Building Permits Survey.
What an Owner Can Build Today
Atlanta's Zoning Ordinance is Part 16 of the City Code. Each residential district has its own chapter, and each chapter lists the uses the district permits. The code was last updated on September 24, 2026, and that version is the one this guide reads.
The R-4 chapter states the single-family rule in plain terms. It says that "in no case shall there be more than one main building and one main use on a lot." The same chapter lists one exception as an accessory use: an accessory dwelling unit, "where the total number of dwelling units on any parcel, including the accessory dwelling unit, does not exceed two." R-4A has the same line. R-1, R-2, R-2A, R-2B, R-3, R-3A and R-4B do not list ADUs.
The R-5 chapter is titled Two-Family Residential. Its first permitted use is a "single-family or two-family dwelling." An R-5 lot can hold a house, a duplex, or a house with an ADU, and the total stays at two homes. The code's definitions treat a building with three or more homes as a multi-family dwelling, and no R district permits one.
The history notes under these chapters end in 2021. The latest is Ord. No. 2021-60, adopted December 15, 2021, which dealt with short-term rentals. No ordinance from 2022 to 2026 changed the number of homes allowed in R-1 to R-5 or RG. The current code also has no rule that allows duplexes or fourplexes near MARTA stations in single-family districts. The duplex, triplex and fourplex page goes through each unit count.
The Districts in One Table
The table lists the ten single-family and two-family districts. Yards are the required distances between a building and the front, side and rear property lines. FAR is the floor area ratio: the floor area of the buildings divided by the area of the lot. Lot coverage is the largest share of the lot that may be covered, as the code defines coverage.
| District | Homes allowed | Minimum lot | Frontage | Front / side / rear yard (ft) | Maximum FAR | Lot coverage | ADU |
|---|---|---|---|---|---|---|---|
| R-1 | 1 house | 2 acres | 200 ft | 60 / 25 / 35 | 0.25 | 25% | No |
| R-2 | 1 house | 1 acre | 150 ft | 60 / 15 / 30 | 0.30 | 35% | No |
| R-2A | 1 house | 30,000 sq ft | 100 ft | 60 / 15 / 30 | 0.35 | 35% | No |
| R-2B | 1 house | 28,000 sq ft | 100 ft | 50 / 10 / 20 | 0.40 | 40% | No |
| R-3 | 1 house | 18,000 sq ft | 100 ft | 50 / 10 / 20 | 0.40 | 40% | No |
| R-3A | 1 house | 13,500 sq ft | 85 ft | 50 / 10 / 15 | 0.45 | 45% | No |
| R-4 | 1 house plus 1 detached ADU (2 homes in total) | 9,000 sq ft | 70 ft | 35 / 7 / 15 | 0.50 | 50% | Yes |
| R-4A | 1 house plus 1 detached ADU (2 homes in total) | 7,500 sq ft | 50 ft | 30 / 7 / 15 | 0.50 (smaller lot of record: the lesser of 3,750 sq ft or 0.65) | 55% of net lot area | Yes |
| R-4B | 1 house | 2,800 sq ft | 40 ft | 20 / 5 / 5 | 0.75 (smaller lot of record: the lesser of 2,100 sq ft or 0.90) | 85% of net lot area | No |
| R-5 | 1 house, a two-family dwelling or duplex, or 1 house plus 1 detached ADU (2 homes at most) | 7,500 sq ft | 50 ft | 30 / 7 / 7 (ADU: 4 ft side and rear) | 0.50 for a house including an ADU; 0.60 for a duplex | 55% of net lot area | Yes |
Source: each district's chapter in the Atlanta Zoning Ordinance, linked from the district name. Height is 35 feet in every district from R-1 to R-5.
Three or more homes on one lot need one of the districts below. Each already exists in the code, and a lot gets one of them only by a rezoning that City Council approves.
| District | Homes allowed | Lot | Yards | Floor area | Height |
|---|---|---|---|---|---|
| RG (RG-1 to RG-5) | Single-family, two-family and multi-family dwellings | Single and two-family lots: 1,000 sq ft of net area, 20 ft wide | Front yard 40 ft | Highest ratio in each sector of the code's table: 0.162, 0.348, 0.696, 1.49 and 3.20 (Sectors 1 to 5) | No fixed limit. A 45-degree height plane applies next to R-1 to R-5, RG-1, RG-2, MR-1, MR-2 and MR-MU land |
| R-LC | Multi-family dwellings, offices and small personal services. Single and two-family dwellings too | Single and two-family lots: 5,000 sq ft, 50 ft wide | Front 30 ft, side 7 ft (20 ft next to a residential district), rear 20 ft | Multi-family follows the Sector 2 ratios | 35 ft |
| MR-1 and MR-2 | Single-family, two-family and multi-family dwellings, and attached homes on their own lots | 2,000 sq ft, 25 ft of frontage | Side 10 ft, rear 10 ft | 0.162 in MR-1, 0.348 in MR-2 | 35 ft |
| MR-MU | At least 4 and at most 12 homes on a lot, in one principal building | 2,000 sq ft, 25 ft of frontage | Side 5 ft, rear 10 ft | Limited by the cap of 12 homes per building | 35 ft |
Sources: Chapter 8 (RG), Chapter 9 (R-LC) and Chapter 35 (MR).
MR-MU is the district the City wrote for missing middle housing, meaning buildings that sit in size between a house and a large apartment block. Ord. No. 2019-09, adopted January 31, 2019, added it to the code with the description "Two- to three-story multi-unit buildings targeting 'Missing Middle' housing needs." The zoning districts page explains every row.
Two, Three or Four Homes: What Each Needs
| Homes | Building | Districts that permit it | Main numbers | In another district |
|---|---|---|---|---|
| 2 | House plus a detached ADU | R-4, R-4A, R-5 | ADU detached, 750 sq ft at most, 20 ft tall at most, and at most 30% of the floor area of the main house. No ADU parking required in R-4 and R-4A. | R-1 to R-3A and R-4B do not list ADUs. A lot there needs a rezoning. |
| 2 | Duplex or two-family dwelling | R-5. Also RG, R-LC, MR and MRC | R-5: 7,500 sq ft lot, 50 ft of frontage, floor area ratio 0.60 for a duplex, 35 ft tall. | Rezoning to R-5. The application fee is $500 for a site of 1 acre or less. |
| 3 | Triplex | RG, R-LC, MR-1, MR-2 and higher MR districts, MRC | RG floor area ratio by sector (0.348 in Sector 2, 0.696 in Sector 3). MR-1 0.162, MR-2 0.348. MR-MU needs at least four homes, so a triplex cannot use it. | Rezoning. A variance cannot grant a use the code prohibits. |
| 4 | Fourplex | MR-MU, RG, R-LC, MR-1, MR-2 and higher MR districts, MRC | MR-MU: 4 to 12 homes on a lot, one principal building, 2,000 sq ft lot, 35 ft tall, 0.5 parking space per home. | Rezoning. The application fee to MR or MR-MU is $500 for a site of 1 acre or less. |
| 5 to 12 | Small apartment building | MR-MU (12 homes per building at most), RG, MR | The affordable housing rules in the BeltLine, Westside and Northwest Atlanta overlays start at 10 new homes. | Rezoning. |
Sources: the district chapters above, and Atlanta Code Sec. 6-1007 for application fees.
The last column matters as much as the first. A variance is permission to depart from a measurement rule such as a yard or a height. Atlanta's variance chapter says "no variance may be granted for a use of land or building or structure that is prohibited by the Zoning Ordinance." A second home on an R-3 lot, or a third on an R-4 lot, is a prohibited use, so the owner must apply for a rezoning. The approvals page explains that process.
The Proposed Rewrite: ATL Zoning 2.0
Everything in this section is proposed. The rewrite ordinance is 26-O-1508. Its meeting history shows it was referred to the Zoning Committee on September 8, 2026, held by the committee on September 14, returned as held by the full Council on September 21, and held again on September 28, 2026. On October 6, 2026 its status read "Held in Committee." The text attached to it is a 981-page file whose cover reads "DRAFT V2 | December 19, 2025."
The draft replaces the R names with form districts. House-scale districts H1 to H6 keep the lot sizes of today's R-1 to R-3A and stay at one home per lot. Neighborhood-scale districts N1 to N6B cover smaller lots. The draft would allow two homes per lot in N2B, N3B and N4B, six in N5A and twelve in N5B.
| Proposed district | Minimum lot | Homes per lot | Maximum FAR | R district with the same minimum lot today |
|---|---|---|---|---|
| H1 | 2 acres | 1 | 0.25 | R-1 |
| H2 | 1 acre | 1 | 0.30 | R-2 |
| H3 | 30,000 sq ft | 1 | 0.35 | R-2A |
| H4 | 28,000 sq ft | 1 | 0.40 | R-2B |
| H5 | 18,000 sq ft | 1 | 0.40 | R-3 |
| H6 | 13,500 sq ft | 1 | 0.45 | R-3A |
| N1 | 9,000 sq ft | 1 | 0.50 | R-4 |
| N2A | 7,500 sq ft | 1 | 0.55 | R-4A, R-5 |
| N2B | 7,500 sq ft | 2 | 0.60 | R-4A, R-5 |
| N3A | 5,000 sq ft | 1 | 0.60 | None |
| N3B | 5,000 sq ft | 2 | 0.65 | None |
| N4A | 2,800 sq ft | 1 | 0.65 | R-4B |
| N4B | 2,800 sq ft | 2 | 0.70 | R-4B |
| N5A | 2,000 sq ft | 6 | None | None |
| N5B | 2,000 sq ft | 12 | None | None |
| N6A | 2,000 sq ft | Unlimited | 1.0 | None |
| N6B | 2,000 sq ft | Unlimited | 1.75 | None |
Proposed. Source: ATL Zoning 2.0 Draft V2, Chapter 2: Form Districts, and the same tables in Exhibit 1 to 26-O-1508 (PDF, 981 pages). The last column compares lot sizes only. The draft zoning map decides which district a lot would receive.
The draft would also change ADUs. It proposes ADUs that are attached or detached, up to 850 square feet each, with the number set by a separate "use district." The ATL Zoning 2.0 page has the status, the ADU and parking tables, and what the City says will stay the same.
Georgia State Law Leaves the Choice to Each City
Georgia has no statewide law that sets how many homes a city must allow on a lot. The Governor's office publishes every signed bill. Its lists for 2025 (351 rows) and 2026 (352 rows) contain no statewide bill on ADUs, lot sizes, missing middle housing or limits on local building moratoriums. House Bill 1166, an ADU bill from the 2026 session, is absent from the 2026 list.
One state law controls how a city may change its own rules. HB 155 (2025) amended Georgia's Zoning Procedures Law, and Part II of the act took effect on July 1, 2025. When a local government amends its zoning ordinance so that single-family districts allow multifamily uses, it must adopt the change at two regular meetings held at least 15 and at most 45 days apart. Before the final vote it must hold at least two public hearings, three to nine months ahead, and one of them must take place between 5:00 P.M. and 8:00 P.M. Georgia law sets this schedule for any such change, in any city.
What the Permit Numbers Show
The City of Atlanta had 529,110 people on July 1, 2025, by the Census Bureau's Vintage 2025 estimate, up from 520,760 a year earlier and 498,805 in the April 1, 2020 estimates base. The Atlanta-Sandy Springs-Roswell metro area had 6,482,182 people.
| Building permits | 1-unit buildings | 2-unit buildings (homes) | 3 to 4 unit buildings (homes) | 5+ unit buildings (homes) |
|---|---|---|---|---|
| City of Atlanta, 2025 | 561 | 78 (156) | 64 (236) | 388 (4,669) |
| City of Atlanta, 2024 | 791 | 51 (102) | 98 (369) | 590 (6,847) |
| Atlanta-Sandy Springs-Roswell metro area, 2025 | 22,065 | 94 (188) | 98 (365) | 585 (11,052) |
| Georgia (statewide), 2025 | 44,351 | 354 (708) | 176 (641) | 814 (15,496) |
Sources: Census Bureau Building Permits Survey annual files for places, 2025, places, 2024, metro areas, 2025 and states, 2025.
In 2025 the City issued permits for 561 one-unit buildings, 78 two-unit buildings, 64 buildings of three or four units and 388 buildings of five or more units. Homes in buildings of two to four units were 392 of the 5,622 homes permitted, or 7.0 percent, by VanPlex's calculation from the Census file. Two-unit buildings rose from 51 in 2024 to 78 in 2025. Buildings of three or four units fell from 98 to 64.
Most of the region's permits for small buildings are issued in the city. Of the metro area's 94 two-unit buildings permitted in 2025, 78 were in the City of Atlanta, and of its 98 buildings of three or four units, 64 were. Decatur, South Fulton, Marietta and Brookhaven each reported zero of both types that year, and so did Sandy Springs in the 11 months it reported. The metro page covers those places.
What Changed Recently
The number of homes per lot in Atlanta's R districts has stayed the same since 2021. Other rules that affect a small project changed between 2023 and 2026.
| Date | What changed | Source |
|---|---|---|
| February 6, 2023 | Decatur ordinance O-23-Z-01 added duplexes and 3 to 4 unit walk up flats to its single-family districts R-85, R-60, R-50 and RS-17. Read more | Decatur UDO, Article 3 |
| July 1, 2024 | Georgia's Safe at Home Act (HB 404) capped security deposits at two months' rent for leases signed or renewed from this date. Read more | HB 404 (2024) |
| February 17, 2025 | The City of Atlanta opted out of the HB 581 statewide homestead exemption by resolution 25-R-3143, adopted 15 to 0. Read more | Resolution 25-R-3143 |
| June 24, 2025 | Atlanta replaced its Tree Protection Ordinance (Ord. No. 2025-19). The payment for each inch of tree removed is $140 from January 1, 2026. Read more | Atlanta Code, Chapter 158, Article II |
| July 1, 2025 | Georgia HB 155 changed the hearing schedule for any local zoning change that lets single-family districts hold multifamily uses. Read more | HB 155 (2025) |
| December 9, 2025 | The Georgia Department of Community Affairs announced that its Board adopted the 2024 International Residential and Building Codes with an effective date of January 1, 2027. Read more | Georgia DCA announcement |
| September 8, 2026 | Ordinance 26-O-1508 (ATL Zoning 2.0) was referred to the Zoning Committee, which held it on September 14 and September 28, 2026. It is proposed, and the 1982 Zoning Ordinance is still the law. Read more | Council file 26-O-1508 |
Atlanta Compared With Texas and California
VanPlex also publishes guides to Texas and California. Georgia and Texas share one feature: the state leaves the number of homes per lot to each city. California writes that rule at the state level.
| Topic | Atlanta and Georgia | Texas | California |
|---|---|---|---|
| State law on homes per single-family lot | None. Atlanta sets the number by zoning district: one house in R-1 to R-4B, two homes in R-5. | None. Each city decides under Local Government Code chapter 211. | SB 9 (2021) requires cities to approve up to two homes on a single-family lot, a split of that lot into two, or both, through staff review with no hearing. |
| State ADU law | None signed in 2025 or 2026. Atlanta allows one detached ADU in R-4, R-4A and R-5. | None. SB 673 (2025) stopped on the House calendar. Its last action was May 26, 2025. | Government Code 66323 requires cities to approve, on a single-family lot, one ADU converted from existing space, one junior ADU inside the house and one new detached ADU. |
| Two-unit buildings permitted statewide in 2025 (homes) | Georgia: 354 (708) | 3,178 (6,356) | 1,748 (3,496) |
| Buildings of 3 to 4 units permitted statewide in 2025 (homes) | Georgia: 176 (641) | 727 (2,777) | 330 (1,137) |
Sources: Georgia signed legislation, 2026, Texas Local Government Code 211.003, Texas SB 673 bill history, California HCD SB 9 Fact Sheet, California Government Code 66323 and the Census Building Permits Survey state file, 2025.
For an Atlanta owner, the right to a second or third home comes from the district on the zoning map or from a rezoning of the lot. Georgia's HB 155 sets the hearing schedule the City must follow if it amends its ordinance to add multifamily uses to single-family districts.
Five Steps to Your Answer
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Step 1
Find your zoning district
Search your address on the City's Atlanta Property Information map. It shows addresses, tax parcels and zoning. The lot eligibility page lists every check.
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Step 2
Read the row for that district
Compare your lot's area and street frontage with the district minimums. In R-1 through R-4B, a lot of record smaller than the minimum may be used only for one single-family house.
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Step 3
Check the site limits
Historic and landmark districts need a certificate of appropriateness for new buildings. Streams have a 75-foot buffer on each side. Regulated trees need a removal permit. See trees and stormwater and the BeltLine Overlay page.
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Step 4
If the district does not permit your plan, look at a rezoning
A rezoning goes to your Neighborhood Planning Unit, the Zoning Review Board and City Council. The application fee to R-5, RG, MR or MR-MU is $500 for a site of one acre or less. Read rezoning, NPU and variances.
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Step 5
Check the code, the fees, the taxes and the loan
Georgia's residential code covers one- and two-family homes and townhouses, so a building of three or four homes that is not townhouses is built under the building code. See permits and building code, impact fees, property tax, landlord rules and financing 2 to 4 units.
Who This Guide Is For
Homeowners
You own a house in the City of Atlanta and want to know if you can add a second home behind it or turn it into a duplex.
ADU rules →Small builders and investors
You look for lots that can hold two to four homes and need to know which districts permit them and which need a rezoning.
Duplex, triplex, fourplex →Architects and permit consultants
You need lot sizes, yards, floor area ratios and code section numbers for each district in one place.
Zoning districts →Best For
- ✓ An R-4, R-4A or R-5 lot where a detached ADU of up to 750 square feet meets your goal.
- ✓ An R-5 lot of 7,500 square feet or more, where a duplex is a permitted use.
- ✓ Land already zoned RG, R-LC, MR or MR-MU, where three or more homes are permitted.
Usually Fails When
- ✕ The lot is zoned R-1 to R-3A or R-4B and the plan needs a second home. Those districts allow one house and list no ADU.
- ✕ The plan counts on a variance to add a unit. The Board of Zoning Adjustment cannot grant a use the code prohibits.
- ✕ The budget or schedule assumes the proposed ATL Zoning 2.0 rules. The ordinance is held in committee.
What To Verify Before Spending Money
- → The zoning district, and any overlay or historic district, on the City's Atlanta Property Information map.
- → Lot area and street frontage against the district minimums.
- → The status of ordinance 26-O-1508 on the City Council legislation site before you rely on any draft rule.
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Frequently Asked Questions
Can I build a duplex on my lot in Atlanta?
How many units can I build on a single-family lot in Atlanta?
What zoning allows a fourplex in Atlanta?
Did Atlanta end single-family zoning?
Has Atlanta's new zoning code passed?
Does Georgia have a state law allowing ADUs everywhere?
Which Atlanta zoning districts allow an ADU?
How do I find out what my Atlanta property is zoned?
How many duplexes and fourplexes were built in Atlanta in 2025?
Do I need to go to my NPU to build a duplex in Atlanta?
What fees does Atlanta charge on a new duplex?
Is Decatur different from Atlanta for duplexes and fourplexes?
Official sources (checked October 2026)
Planning a multiplex in Atlanta?
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