ADU Craft Jacksonville

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ADU types we build in Jacksonville

Four kinds of second unit, one team from survey to final inspection. Your lot's elevation and what is already on it usually point to the right one.

Small backyard home (ADU): A wooden bench sitting on top of a grass covered field Backyard ADU (detached)A new small house in the rear yard. Full control of layout and floor height. Detached garage Garage conversionLiving space inside an existing garage, where its floor elevation allows. Small backyard home (ADU) In-law suite (attached)An addition with its own door and kitchen, sharing a wall with the house. Detached garage Garage apartmentA second-floor unit over a garage, tied to the main house's height.

ADU design and permits

Survey, plans, wind and flood engineering, the city review and every correction until the permit is issued.

How design and permits work

Which ADU type should I pick?

Let the lot decide first. In Jacksonville that means three questions: is there room behind the house, is there a garage worth reusing, and how high does the flood map say living space must sit. The answers often narrow four types down to one or two.

Then think about who will live there. A tenant wants a private entrance and a quiet yard. A parent may prefer an in-law suite a few steps from your kitchen.

What does the City of Jacksonville allow?

As of October 2026, the 2022 ordinance permits one ADU on most conforming low-density residential lots. Reporting on the ordinance described its main limits: the ADU sits behind the main house, cannot be taller than it, and its footprint is held to 25% of the main home's gross floor area or 750 sq ft, whichever is less. The owner must live on the property.

How do the four types compare here?

  • Backyard ADU: the most privacy; must stay behind the house and inside the footprint cap.
  • Garage conversion: often the lowest cost, but only if the slab sits high enough for living space under flood rules.
  • In-law suite: joined to the house; on a flood-zone lot, a large addition can pull the whole house into flood compliance.
  • Garage apartment: parking below and living space above, which can help on low lots; the height cap tied to the main house applies.

Which type costs the least?

It depends on what you start with. Reusing a sound garage that already sits above flood level is usually cheapest. On a low lot, the conversion can lose that edge because the floor has to come up. Building new costs more but gives you full control of elevation. The cost guide has published ranges.

Rules as of October 2026, from reporting on City of Jacksonville Ordinance 2022-0448 (Jacksonville Daily Record, Jacksonville Today). Confirm current wording with the city's Zoning Section.

Check what your lot allows

Share the address and your idea. We find out which government issues the permit, then check zoning, flood zone, covenants and setbacks, and tell you which ADU types are realistic.

Serving Jacksonville, Jacksonville Beach, Orange Park, St. Augustine and Fernandina Beach.