MIAMI 21 RULES

What the Miami 21 code allows.

Miami's zoning code — Miami 21 — permits ADUs on most T3-zoned (single-family) lots through Section 3.13. The framework is one of the most permissive in Florida:

Max ADU size: 800 sq ft, no more than 50% of the primary dwelling.
Setbacks: 5 ft side, 10 ft rear (subject to existing structure rules).
Height limit: 25 ft.
Owner-occupancy required: the property owner must live in either the main house or the ADU.
Parking: one off-street space for the ADU.
Short-term rental (under 30 days): not permitted in T3 zones for ADUs.

Miami-Dade unincorporated areas follow the County's separate ADU ordinance — similar in spirit but with different setback and lot-size requirements. If your address is in unincorporated Miami-Dade (not within a municipal limit), refer to Miami-Dade County housing.

THE NUMBERS

What a Tooly costs in Miami, all-in.

Tooly unit (delivered, furnished, finished)	$85,000
Miami building permit + impact fees	$3,500 – $6,500
Foundation + site prep	$12,000 – $20,000
Utility tie-ins (water, sewer, electrical)	$6,000 – $14,000
Total installed cost	$106,500 – $125,500

Miami rental economics

Furnished 1-bedroom long-term rents in Miami's mid-tier neighborhoods (Little Havana, Allapattah, West Coconut Grove, Brownsville) sit at $1,600–$1,950/month. In high-tier neighborhoods (Coral Gables, Coconut Grove, Edgewater), 1-bed rents push past $2,300. A Tooly in either market produces strong cash flow — see the rental income page for the full breakdown.

PERMIT PROCESS

How to get an ADU permit in Miami.

Pre-application zoning verification — confirm your lot is T3 or higher. Free, online via Miami's Planning Department portal.
Submit building permit application — drawings, structural calcs, site plan. Tooly provides the structural and architectural package.
Review and revision — typically 4–8 weeks of city review with comments.
Permit issued — construction can begin.
Inspections — foundation, framing, electrical, plumbing, final.
Certificate of occupancy — you can move in or rent.

Total realistic timeline from contract to move-in: 15–22 weeks depending on city queue.

Miami homeowners — your backyard is a business.

Tell us your address. We'll confirm Miami 21 eligibility and come back with a permit-ready quote in 48 hours.

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