Miami-Dade, FL · Updated 2026

Miami-Dade ADU Permits: Fees, Timeline & Process

171,000+ eligible properties — pre-approved plans, hurricane code compliance, and Certificate of Use requirements.

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Miami-Dade ADUs: $100K–$200K

Permits: $4.5K–$15K · Updated April 2026

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Miami-Dade ADU Permitting: Overview

Miami-Dade County's 2022 ADU reforms opened 171,683 single-family properties to ADU construction. The county permits ADUs in AU, EU, RU, and GU zoning districts within the Urban Development Boundary, with a minimum lot size of 7,500 square feet. All ADU plans must be sealed by Florida-licensed engineers or architects and meet hurricane-resistant construction standards.

Miami-Dade offers a pre-approved ADU Blueprint program that can reduce permit wait times by up to 40%. Unlike most other markets, Miami-Dade requires a Certificate of Use (CU) for legal ADU occupancy — this must be obtained and renewed annually by the property owner. RU-1 zoned ADUs are limited to 400–800 sq ft with strict setback requirements.

Permit Fees Breakdown

Total permitting costs in Miami-Dade typically range from $4,500–$15,000 depending on ADU type, size, and site conditions.

Fee TypeAmountNotes
Building Permit$1,500–$4,000Valuation-based per Building Fee Schedule
Plan Review40% of permitIncluded in total permit cost
Impact Fees$3,000–$8,000Transportation, schools, fire, parks
Utility Connections$2,500–$6,000Water, sewer, electrical service
Certificate of Use$100–$300/yrRequired annually for legal occupancy
Tree Removal PermitVariesIf protected trees require removal
Flood Zone ComplianceVariesAdditional engineering if in flood zone

Fees are estimates based on typical ADU projects. Contact Miami-Dade permitting for exact quotes. See our full permit fees guide for comparison across cities.

Zoning & Requirements

  • ADUs permitted in AU, EU, RU, and GU zoning districts
  • Must be within the Urban Development Boundary
  • Minimum lot size: 7,500 square feet
  • RU-1 max size: 400–800 sq ft
  • Minimum habitable area: 220 sq ft
  • Must meet hurricane-resistant construction standards (High Velocity Hurricane Zone)
  • Certificate of Use required for legal occupancy
  • Owner disclosure statement required with all applications

Step-by-Step Permit Process

1

Verify property eligibility

Check Miami-Dade Land Management for zoning, lot size (7,500 sf min), Urban Development Boundary status, and approved land uses.

2

Choose design approach

Select from Miami-Dade's pre-approved ADU Blueprint program (faster review) or commission custom plans sealed by a FL-licensed professional.

3

Prepare permit package

Complete building permit application, ADU owner disclosure statement, Hold Harmless form (if pre-approved), sealed architectural/structural/MEP plans, and site plan.

4

Submit application

Upload documents to Miami-Dade's online building permit portal.

5

Plan review (4–12 weeks)

Zoning, building, structural, and fire departments review. Florida Statute 553.792 requires response within 30 business days or fees are reduced.

6

Pay fees & obtain permit

Pay building permit, impact fees, and any applicable utility connection charges.

7

Construction & inspections

Foundation, framing, trades, and final inspections. Hurricane tie-down and wind resistance inspections are particularly important in Miami-Dade.

8

Obtain Certificate of Use

After final inspection, apply for a Certificate of Use — required for legal ADU occupancy in Miami-Dade. Must be renewed annually.

Key Regulations & Laws

2022 ADU Reforms

Opened 171,683 single-family properties to ADU construction by expanding eligible zoning districts within the Urban Development Boundary.

Florida Statute 553.792

Counties must respond to permit applications within 30 business days or reduce fees. Provides a timeline guarantee.

Pre-Approved Blueprint Program

Miami-Dade offers pre-approved ADU designs that reduce permit review times by up to 40%.

SB 48 / HB 313 (Expected 2026)

Proposed Florida legislation would require all counties to allow ADUs statewide, further expanding opportunities.

High Velocity Hurricane Zone (HVHZ)

Miami-Dade ADUs must meet enhanced structural requirements for hurricane resistance, including impact-rated windows and reinforced connections.

Frequently Asked Questions

How much does an ADU permit cost in Miami-Dade?

Building permit fees run $1,500–$4,000 based on construction valuation. Including impact fees and utility connections, total permit costs range from $4,500–$15,000. The Certificate of Use adds $100–$300 annually.

How long does ADU permitting take in Miami?

Plan review typically takes 4–12 weeks. Pre-approved Blueprint designs are faster. Florida law requires county response within 30 business days. The full project typically takes 8–14 months.

Do I need a Certificate of Use for my ADU?

Yes. Miami-Dade requires a Certificate of Use for legal ADU occupancy. It must be obtained after final inspection and renewed annually by the property owner. It does not transfer automatically when the property is sold.

What makes Miami-Dade ADU construction different?

Hurricane code compliance is the biggest differentiator. ADUs must meet High Velocity Hurricane Zone (HVHZ) standards, including impact-rated windows, reinforced roof-to-wall connections, and enhanced structural engineering. This adds cost but ensures safety.

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