ADU permit comparison — all cities
| City + state | Permit type | Max size | Owner occupancy | Parking | Setback minimums | Permit fees | Plan review timeline | State preemption framework | Full city guide |
|---|---|---|---|---|---|---|---|---|---|
| Atlanta, GA | Residential building permit through the Atlanta Office of Buildings, filed via the Atlanta Permitting Portal. Both attached ADUs… | The smaller of 750 square feet of gross floor area or 50% of the gross floor area of the primary dwelling. If the… | Not required. Atlanta's 2023 zoning update does not require the property owner to reside on site as a condition of… | One off-street parking space is required for the ADU. Verify whether the specific parcel or zone qualifies for a parking reduction with… | Detached ADU: minimum 5-foot rear setback. Side setbacks follow the standard requirements for the applicable residential zone district.… | $500–$1,800 estimated combined fees (permit + plan review) for a typical new ADU in Atlanta; excludes any Historic Preservation review or variance… | 10–20 business days for standard residential plan review | Georgia SB 70 (enabling; not full preemption) | Full guide |
| Austin, TX | Separate residential new-construction / addition permit for a dwelling unit, filed through Austin Build + Connect rather than treated… | Austin's ADU guidance does not publish one simple citywide ADU square-foot cap. It says required size is based on… | Austin's ADU and HOME pages reviewed for this page do not headline a standalone owner-occupancy requirement for the… | Austin's ADU guidance reviewed here does not publish a universal citywide parking waiver for all ADUs. Confirm parking, access, and… | Austin says zoning no longer requires a minimum distance between units. Base zoning setbacks, site-development rules, and IRC /… | Austin does not publish a simple flat ADU fee on the ADU page; plan review fees are generated at submittal and permit fees are generated at… | 15 business days per initial new-construction review cycle | Texas HB 2127 context | Full guide |
| Boston, MA | Residential building permit through Boston Inspectional Services Department (ISD), filed in person at 1010 Massachusetts Avenue. Both… | 900 square feet of gross floor area, or the gross floor area of the principal dwelling unit, whichever is smaller.… | Required under Article 25. The property owner must reside in the principal dwelling or the ADU. This is a meaningful… | One off-street parking space is required for the ADU unless the lot is within a Boston Transit Overlay District, in which case no… | The ADU must comply with the setback requirements of the underlying zoning subdistrict. Boston's residential subdistricts typically… | $650–$1,900 estimated combined fees (building permit + plan review + state surcharge) for a typical new ADU in Boston; excludes any ZBA variance or… | 5–15 business days for standard residential plan review | No statewide preemption; Boston Article 25 controls | Full guide |
| Charlotte, NC | Charlotte routes ADUs through concurrent City and County review: a City of Charlotte zoning / land-development review (LDIRL / zoning… | Charlotte's public ADU overview does not publish a single citywide one-line size cap. Detached ADUs must fit the… | Charlotte's public ADU page says the ADU must stay under the same ownership as the main home. The overview page does… | Charlotte reviews parking and access as part of parcel-level feasibility. The public ADU overview does not give a single universal parking… | Under Charlotte UDO Article 17, accessory structures generally cannot sit in the front or corner-side setback. In a side or rear setback… | $1,750–$6,500+ in combined city/county permit and trade-permit fees is a reasonable Charlotte ADU planning range before utility-connection or… | 15–30 business days for straightforward reviews, longer if land-development comments or overlays apply | See city guide | Full guide |
| Chicago, IL | See city guide | See city guide | See city guide | See city guide | See city guide | $1,500–$6,500+ is a realistic Chicago planning range for a compliant ADU once pre-certification, DOB permit review, and trade permits are included | 15–35 business days once the pre-certification package and permit drawings are complete | See city guide | Full guide |
| Dallas, TX | Residential new construction building permit filed through the DallasNow Accela portal (aca-prod.accela.com/DALLASTX/Default.aspx).… | 1,500 square feet of gross floor area, or 50 percent of the gross floor area of the primary dwelling, whichever is less. | Dallas Development Code Article IV does not impose a blanket owner-occupancy requirement for ADUs in the base… | One additional off-street parking space is required for an ADU. The space must comply with Dallas Development Code dimensional and… | 5 feet from rear and interior side property lines. Front-yard setbacks follow the base zoning district standard. Setbacks from easements… | $1,500–$4,500+ in combined city permit, plan review, and trade permit fees is a practical Dallas ADU planning range before site, utility, or HOA costs | 7–10 business days for initial residential plan review | Texas HB 2127 context | Full guide |
| Denver, CO | Residential building permit (new construction or addition) through Denver Building & Fire Code, with concurrent zoning review by… | DADU: 864 square feet of gross floor area, or 50% of the primary dwelling's gross floor area, whichever is greater… | No owner-occupancy requirement under Denver Zoning Code 5.4. Colorado HB24-1152 (2024) also prohibits municipalities… | No additional off-street parking is required for an ADU in Denver's urban and suburban zone districts under current Denver Zoning Code… | DADU: minimum 5 feet from rear lot line and 5 feet from each side lot line under Denver Zoning Code 5.4. Front setback must meet the… | Denver permit and plan review fees are valuation-based. A new detached ADU valued at $150,000–$250,000 typically generates $2,000–$5,000+ in… | 4–8 weeks for standard plan review; concurrent review by zoning and building is standard practice | Colorado HB24-1152 | Full guide |
| Detroit, MI | Residential building permit through the Detroit Buildings, Safety Engineering and Environmental Department (BSEED), submitted via the… | 600 square feet of floor area, and the ADU cannot exceed the floor area of the principal dwelling. Detroit's Chapter… | Required. Detroit's ADU ordinance requires the property owner to reside in either the principal dwelling or the ADU as… | Detroit's ADU standards do not expressly waive parking requirements. The underlying zoning district's parking requirements still apply to… | The ADU must comply with the setback standards of the applicable residential district under Detroit's Zoning Ordinance. Detached ADUs are… | $600–$2,400+ estimated combined BSEED permit and plan review fees for a typical Detroit ADU; trade permits and any BZA variance costs are additional | 10–25 business days for standard residential plan review through BSEED ePLANS | See city guide | Full guide |
| Houston, TX | Residential new construction building permit through Houston Permitting Center (houstonpermittingcenter.org). Houston treats an ADU… | Houston has no citywide zoning ordinance, so there is no city-imposed maximum ADU floor area. Deed restrictions… | Houston's building permit process does not impose an owner-occupancy requirement for ADUs. No citywide zoning rule… | Houston has no citywide parking-space requirement for ADUs in residential contexts under the building code framework. Deed restrictions… | Houston has no general citywide zoning setback ordinance for residential lots. The Houston Building Code and 2021 IRC structural fire… | $1,200–$4,000+ in combined city permit, plan review, and trade permit fees is a practical Houston ADU planning range before deed-restriction review… | 10–15 business days for initial residential plan review | Texas HB 2127 context | Full guide |
| Jacksonville, FL | See city guide | See city guide | See city guide | See city guide | See city guide | $1,850–$7,000+ is a realistic Jacksonville planning range if your project qualifies as permitted accessory living quarters and moves through normal… | 10–25 business days for a straightforward qualifying project, longer if zoning interpretation or floodplain issues arise | See city guide | Full guide |
| Los Angeles, CA | Separate LADBS ADU permit / plan-check path governed by LAMC 12.22 A.33 and state ADU law, not a simple accessory-structure filing. | California state law requires local rules to allow attached ADUs of at least 850 square feet (or 1,000 square feet for… | California HCD says local agencies generally cannot impose owner-occupancy requirements on ADUs. JADUs are different… | LADBS says no parking is required for a new ADU within a half-mile walking distance of public transit, and replacement parking is not… | State ADU law generally limits side and rear setbacks for many newly constructed ADUs to no more than 4 feet. No new setback is required… | Los Angeles ADU fees are project-specific; verify current permit, plan-check, and utility costs with LADBS and the applicable utility departments… | Varies by LADBS review path and correction rounds | California ADU law (SB 897 / AB 2221 / SB 9) | Full guide |
| Miami, FL | See city guide | See city guide | See city guide | See city guide | See city guide | $2,500–$10,000+ is a realistic Miami planning range for a compliant ADU once zoning, building review, trade permits, and HVHZ-related design costs… | 14 business days for a straightforward building review; around 35 business days when the project functions like a special permit or needs broader planning/zoning handling | See city guide | Full guide |
| Minneapolis, MN | Residential building permit through Minneapolis Community Planning and Economic Development (CPED) / Development Services, submitted… | 1,000 square feet of floor area for detached ADUs, or the floor area of the principal dwelling, whichever is smaller.… | Not required. The Minneapolis 2040 Plan eliminated owner-occupancy requirements for ADUs, aligning Minneapolis with… | Minneapolis's 2040 Plan removed minimum parking requirements in most of the city, including most residential zones. There is generally no… | ADUs must comply with the setback standards of the applicable residential zoning district. Detached ADUs are typically located in the rear… | $650–$2,500+ estimated combined permit and plan review fees for a typical Minneapolis ADU; trade permits, heritage preservation review, and… | 10–20 business days for standard residential plan review through Minneapolis ePermits | See city guide | Full guide |
| Nashville, TN | Metro Nashville residential building permit reviewed by Metro Codes and Building Safety, with zoning examiner review of DADU… | Living space is capped at 700 square feet on lots under 10,000 square feet, or 850 square feet on lots of 10,000… | The DADU must be owned by the same person as the principal structure, and one of the two dwellings must be… | Metro's DADU summary page focuses on zoning eligibility, setbacks, massing, and use controls rather than a separate blanket parking… | For a DADU at the rear of the lot with an 850-square-foot-or-smaller footprint, minimum side setback is one-half of the district side… | $1,750–$6,500+ in city permit and trade-permit fees is a practical Nashville DADU planning range before overlay, survey, or site-work costs | 15–30 business days for a straightforward Metro path, longer if overlays or Planning review apply | See city guide | Full guide |
| Oakland, CA | Dual city review through Oakland Planning + Oakland Building Bureau. All ADUs require planning and building permits, even when state… | Oakland's local category rules sit under California state ADU law. Detached ADUs must still fit the statewide… | California state ADU law generally bars local owner-occupancy mandates for full ADUs. JADUs remain different and can… | State law sharply limits Oakland's ability to require ADU parking. Replacement parking is generally not required when converting covered… | Oakland applies its Planning Code and zoning criteria, but California state law limits side and rear setbacks for many new ADUs to no more… | $3,000–$10,000+ is a realistic combined planning, building, and trade-permit range for a typical Oakland ADU; legalization or major utility work can… | Varies by track; straightforward projects are typically reviewed in weeks, while legalization, overlay, or correction-heavy projects can stretch materially longer | California ADU law (AB 2221 / SB 9) | Full guide |
| Philadelphia, PA | Residential building permit through the Philadelphia Department of Licenses and Inspections (L&I), submitted via the eCLIPSE online… | Philadelphia's Zoning Code does not specify a single universal ADU square footage cap; size is governed by the… | Not required. Philadelphia's ADU ordinance does not impose an owner-occupancy condition — the property owner is not… | Philadelphia's ADU zoning does not impose a separate off-street parking requirement for the ADU unit. However, the underlying zoning… | ADUs must comply with the setback standards of the applicable zoning district. RSA-5 and CMX-1 districts typically have rear and side… | $550–$1,600+ estimated combined L&I permit and plan review fees for a typical Philadelphia ADU; trade permits, ZBA variance proceedings, and… | 10–20 business days for standard residential plan review through eCLIPSE | See city guide | Full guide |
| Phoenix, AZ | See city guide | See city guide | See city guide | See city guide | See city guide | $1,500–$6,500+ is a realistic Phoenix planning range for an ADU permit package including building review, plan check, and trade permits | 10–20 business days for a complete residential ADU submittal | See city guide | Full guide |
| Portland, OR | Residential building permit through Portland Bureau of Development Services (BDS). Attached and detached ADUs both follow the… | 800 square feet of living area or 75% of the living area of the primary dwelling, whichever is less. Garage and… | No owner-occupancy requirement. Portland removed this requirement in 2018. Oregon HB 2001 (2019) further prohibits… | No additional parking required for an ADU. Portland eliminated its ADU parking requirement prior to statewide mandate. | Detached ADU: rear setback of 5 feet; side setbacks per base zone (typically 3–5 feet depending on the zone). Front setback must meet the… | Portland BDS permit and plan review fees are valuation-based. A new detached ADU valued at $150,000–$250,000 commonly generates $2,000–$5,000+ in… | 4–8 weeks for standard plan review; over-the-counter review may be available for simple attached ADU conversions | Oregon HB 2001 | Full guide |
| Sacramento, CA | Community Development permit path through Sacramento's planning + building workflow. State law makes the ADU path ministerial when… | Sacramento follows California's statewide ADU baseline: detached ADUs within the ministerial framework up to 1,200 sq… | California state law generally prevents Sacramento from imposing owner-occupancy on full ADUs. JADUs remain the… | State law sharply limits when Sacramento can require ADU parking. Conversion projects, transit-near lots, and several other common ADU… | California state law limits many new ADU side and rear setbacks to 4 feet. Sacramento still reviews objective standards under Title 17… | $2,500–$8,000+ is a realistic combined permit and trade-fee range for a typical Sacramento ADU; legalization and substantial corrective work can… | Varies by track; standard ministerial ADUs are generally reviewed in weeks, while legalization, historic-property, or correction-heavy files take longer | California ADU law (AB 2221 / SB 9) | Full guide |
| San Antonio, TX | Residential building permit filed through BuildSA / San Antonio Development Services. The city says the application package should… | Up to 800 square feet or 50% of the size of the main house, whichever is larger, but never more than 1,600 square… | The property owner must live either in the main house or in the ADU. San Antonio requires an owner-occupancy affidavit… | Only ADUs over 800 square feet need one dedicated off-street parking space. | Detached ADUs may be as close as 3 feet from side and rear property lines. If you build that close, you cannot have an eave overhang… | $1,500–$4,500+ in combined city permit, plan review, and trade permit fees is a practical San Antonio ADU planning range before utility connection… | 10–15 business days for initial residential plan review | Texas HB 2127 context | Full guide |
| San Diego, CA | City of San Diego DSD residential building permit, submitted through the Permit Technology System (PTS) online portal at… | California state law sets the floor: attached ADUs of at least 850 sq ft (or 1,000 sq ft for 2+ bedrooms) and newly… | California state law prohibits local agencies from imposing owner-occupancy requirements on ADUs through at least 2030… | Replacement parking is not required when a covered space or garage is converted to build an ADU. New parking is not required for an ADU… | State ADU law limits side and rear setbacks for newly constructed ADUs to no more than 4 feet. No setback is required for ADUs or JADUs… | $2,500–$8,000+ is a realistic combined city permit, plan check, and trade permit range for a typical San Diego ADU; Coastal Overlay Zone projects… | 15–30 business days for standard DSD residential plan review; state-law ministerial ADUs have a 60-day statutory approval deadline under California Government Code § 65852.2 | California ADU law (SB 897 / AB 2221 / SB 9) | Full guide |
| San Francisco, CA | Dual-agency process: SF Planning Department ADU Screening (or Waiver or CUA) followed by DBI building permit. Planning clearance is… | California state law requires local rules to allow new detached ADUs up to 1,200 sq ft and attached ADUs of at least… | California state law prohibits local agencies from imposing owner-occupancy requirements on ADUs through at least… | Replacement parking is not required when an existing garage or covered space is converted to build an ADU. New parking is not required for… | State ADU law limits side and rear setbacks for newly constructed ADUs to no more than 4 feet. ADUs or JADUs created entirely within… | $3,000–$12,000+ is a realistic combined planning, building permit, and trade permit range for a typical San Francisco ADU; Rent Ordinance costs are… | 15–45 business days for standard DBI residential plan review; ministerial state-law ADU track may qualify for a 60-day statutory deadline under California Government Code § 65852.2 | California ADU law (AB 2221 / SB 9) | Full guide |
| San Jose, CA | Planning, Building & Code Enforcement permit path through SJPermits / SJePlans. San José requires applicants to start with the ADU… | San José follows California's ADU preemption floor: detached ADUs must fit the statewide ministerial framework up to… | California state law generally prevents San José from imposing owner-occupancy on full ADUs. JADUs remain the… | State law limits when San José can require parking for an ADU. Conversions, transit-near sites, and several other common ADU situations… | The city's checklist controls the practical zoning review, but California state law caps many new ADU side and rear setbacks at 4 feet.… | $3,000–$9,000+ is a realistic combined permit and trade-fee range for a typical San José ADU, with a major fee break for keeping the unit under 750… | Varies by review path and correction rounds; simple or preapproved paths move faster than standard custom ADUs | California ADU law (AB 2221 / SB 9) | Full guide |
| Seattle, WA | Residential building permit (new construction or addition) through Seattle DCI. AADU and DADU both follow the standard residential… | DADU: 1,000 square feet of gross floor area, maximum 24 feet in height under SMC 23.44.041. AADU size is limited to no… | No owner-occupancy requirement. Washington HB 1337 (2023) prohibited cities from requiring the property owner to live… | No additional off-street parking is required for an ADU under Seattle zoning. Existing required parking serving the primary dwelling must… | DADU: minimum 5 feet from rear lot line and 5 feet from each side lot line per SMC 23.44.041. Front setback must meet the standard zone… | Seattle DCI permit and plan review fees are valuation-based. A detached ADU valued at $150,000–$250,000 typically generates $2,000–$5,000+ in… | 10–20 business days for standard residential plan review; over-the-counter review may be available for simple projects | Washington HB 1337 | Full guide |
| Washington, DC | Residential building permit through the DC Department of Buildings (DOB), filed online through the DC Access portal. DC terminology… | DC's 2016 Zoning Rewrite governs accessory apartment size through the subordinate-use standards in 11 DCMR. The… | Not required. DC's 2016 Zoning Rewrite explicitly removed the owner-occupancy requirement that had applied to… | Additional off-street parking is generally not required for an accessory apartment in DC's urban residential zones. Verify whether the… | Accessory apartments must comply with the rear yard and side yard setback requirements of the applicable 11 DCMR subtitle for the zone… | $1,100–$2,700 estimated combined fees (permit + plan review + technology surcharge) for a typical new accessory apartment in Washington, DC… | 4–8 weeks for standard plan review; DOB posts current queue estimates at dob.dc.gov | N/A — DC local code only | Full guide |
Summarized from official sources. Verify with your city before building.
City guides
- Atlanta, GA — ADU permit guide
- Austin, TX — ADU permit guide
- Boston, MA — ADU permit guide
- Charlotte, NC — ADU permit guide
- Chicago, IL — ADU permit guide
- Dallas, TX — ADU permit guide
- Denver, CO — ADU permit guide
- Detroit, MI — ADU permit guide
- Houston, TX — ADU permit guide
- Jacksonville, FL — ADU permit guide
- Los Angeles, CA — ADU permit guide
- Miami, FL — ADU permit guide
- Minneapolis, MN — ADU permit guide
- Nashville, TN — ADU permit guide
- Oakland, CA — ADU permit guide
- Philadelphia, PA — ADU permit guide
- Phoenix, AZ — ADU permit guide
- Portland, OR — ADU permit guide
- Sacramento, CA — ADU permit guide
- San Antonio, TX — ADU permit guide
- San Diego, CA — ADU permit guide
- San Francisco, CA — ADU permit guide
- San Jose, CA — ADU permit guide
- Seattle, WA — ADU permit guide
- Washington, DC — ADU permit guide
Compare other permit types
Disclaimer: Aggregated from official city sources for reference only — not legal advice. Verify with your city before you build.