Miami ADU permit requirements
Last reviewed: June 22, 2026
Quick answer
Permitting an accessory dwelling unit (ADU) in Miami, Florida means pulling a building permit from the local authority that issues it. ArchPermit tracks 15 source-cited requirements (8 required, the rest conditional) for this jurisdiction. Submittals go through iBuild + ePlan / ProjectDox. These requirements were last reviewed June 22, 2026; confirm the exact forms and fees with the local permitting authority.
A source-cited checklist of what an ADU (accessory dwelling unit) permit package needs in City of Miami. Every item links to its authoritative source; items that vary are flagged to confirm locally.
The City of Miami publishes no ADU-specific submittal checklist. What other cities call an ADU is an 'Ancillary Unit' under the Miami 21 zoning code, built as a standard new residential structure under a normal building permit (iBuild + ProjectDox). Ancillary units are permitted by-right in T3-L and T4 zones (not T3-R/T3-O under the adopted code), max 450 sf, single-family use, rentable only if the principal-dwelling owner resides on site, with one parking space. Miami is entirely within the Florida Building Code High-Velocity Hurricane Zone (HVHZ). NOTE: most 'Miami ADU' information online is Miami-Dade COUNTY, a separate jurisdiction whose rules do not apply within city limits. Confirm the exact submittal set with the Building Department.
- Ancillary-Unit Parking Spacerequired
Minimum one parking space per ancillary dwelling unit (T3/T4 per Miami 21 use regulations).
source · reviewed 2026-06-22 - Ancillary-Unit Size Compliance (≤450 sf)requiredverify locally
Documentation that the unit is ≤450 sf (excluding garage) per Miami 21 T3 supplemental regulations. Confirm the current figure on live Municode.
source · reviewed 2026-06-22 - Architectural Plan Sheetsrequiredverify locally
Floor plans, elevations, and sections for the new ancillary structure. Standard for any new-structure permit; not enumerated on an ADU-specific City page.
source · reviewed 2026-06-22 - Boundary / Property Surveyrequiredverify locally
Current survey showing the lot, existing principal building, and proposed unit location for zoning setback/placement review. Standard new-structure item; not on a City ADU-specific page.
source · reviewed 2026-06-22 - Signed & Sealed Construction Plans (PDF)required
Plans signed and sealed by a Florida-registered architect/engineer, uploaded as PDF to ProjectDox per the City's file-naming standards.
source · reviewed 2026-06-22 - Site Plan (Miami 21 zoning compliance)requiredverify locally
Site plan demonstrating Miami 21 compliance: setbacks, lot coverage, placement, and the required ancillary-unit parking space.
source · reviewed 2026-06-22 - Structural Plans / Calculations (HVHZ wind)requiredverify locally
Structural drawings and wind-load calcs meeting Florida Building Code HVHZ requirements. Inferred from Miami's HVHZ status; no City ADU page states it explicitly.
source · reviewed 2026-06-22 - iBuild Permit Applicationrequired
New building-permit application started electronically in the iBuild portal; all new applications must begin here.
source · reviewed 2026-06-22 - Electrical Sub-Permitconditional
Separate electrical sub-permit for the new unit's wiring.
source · reviewed 2026-06-22 - Historic Certificate of Appropriatenessconditional
If the property is in a historic district, a Certificate of Appropriateness applies before/with the building permit.
source · reviewed 2026-06-22 - Mechanical (HVAC) Sub-Permitconditional
Separate mechanical sub-permit for HVAC.
source · reviewed 2026-06-22 - Owner-Occupancy / Single-Family-Use Complianceconditionalverify locally
Showing the unit is a single-family-residence dwelling, rentable only with the owner on site. A code condition; the City has not published a specific affidavit form.
source · reviewed 2026-06-22 - Plumbing Sub-Permitconditional
Separate plumbing sub-permit (an ancillary unit requires a kitchen sink and bathroom).
source · reviewed 2026-06-22 - Product Approvals / Notice of Acceptance (NOA)conditional
Miami-Dade NOA or FL Product Approval for windows, doors, roofing, and other regulated assemblies (HVHZ). Required where such products are used.
source · reviewed 2026-06-22 - Tree Permit / Dispositionconditional
Required if construction affects protected trees on the lot or right-of-way.
source · reviewed 2026-06-22
Miami ADU permit questions
- Do I need a permit to build an ADU in Miami?
- Yes. An accessory dwelling unit (ADU) in Miami requires a building permit. ArchPermit tracks 15 cited requirements for this jurisdiction (8 required, the rest conditional). Always confirm the exact forms, fees, and code edition with the local permitting authority that issues the permit.
- What does an ADU permit package require in Miami?
- Core required items include: Ancillary-Unit Parking Space; Ancillary-Unit Size Compliance (≤450 sf); Architectural Plan Sheets; Boundary / Property Survey; Signed & Sealed Construction Plans (PDF); Site Plan (Miami 21 zoning compliance), plus 2 more. Each requirement links to its authoritative source, and nothing is permit-ready until an independent licensed professional reviews and seals it.
- How are ADU permits submitted in Miami?
- Miami accepts permit submittals via iBuild + ePlan / ProjectDox. ArchPermit prepares a draft package you can submit there after a licensed architect reviews and seals it.