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Efficiency apartments in Miami

A compact studio unit with its own bath and kitchen. Many Miami homes already have one; we help you build a new efficiency or bring an existing one into the permit system.

Check my lot Legalizing an efficiency

What counts as an efficiency in Miami?

Locally, "efficiency" usually means a studio unit with a kitchenette and bathroom, often carved out of a garage, a back room or a separate structure. To be a legal ADU it still needs what an ADU requires: a place to sleep, a full bathroom, a kitchen and its own entrance.

How small can it be?

In unincorporated Miami-Dade, the RU-1 range is 400 to 800 sq ft, and county coverage of the ordinance cited a 220 sq ft minimum of habitable area, as of October 2026. City codes set their own numbers. We design to whichever applies.

Can I permit an efficiency that already exists?

In unincorporated Miami-Dade, the county ADU process covers both building and legalizing a unit. The checklist includes a building permit, an administrative site plan review, impact fees, an owner disclosure statement and a Certificate of Use. Read the legalization guide for the steps.

What does an older efficiency usually need?

Windows and doors with hurricane product approval, or approved shutters.
Smoke alarms, an emergency escape opening in the sleeping area and fire separation from the main house.
Electrical work brought up to code, often on its own circuits.
Plumbing and drainage checked and permitted.
A floor at or above the required flood elevation, if the lot is in a flood zone.

Is there an ongoing county requirement?

Yes, in unincorporated areas. The county says the ADU Certificate of Use must be renewed whether or not the unit is rented, and only the property owner may obtain it. Exterior inspections happen at renewal.

Is legalizing cheaper than building new?

It depends on what is behind the walls. An efficiency built with permitted framing and wiring can be inexpensive to bring up to code. One with unknown wiring, no fire separation and a floor below flood elevation can cost as much as starting over. We open the conversation with an inspection, not a promise.

Check what your lot allows

Tell us whether the efficiency exists already or is a new idea. We start with the county or city rules for your address.