ADU Craft Houston

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ADU types we build in Houston

Four kinds of second unit, plus design and permitting. What fits depends on your restrictions, your flood zone and what already stands on the lot.

Small backyard home (ADU) Backyard cottage (detached ADU)A new building of its own. The most privacy, and the most foundation and utility work. Detached garage Garage apartmentA unit over a new or rebuilt garage, keeping parking on the ground floor. Detached garage: White wooden house near green grass field Garage conversionTurns an existing detached garage into living space, if the slab and framing are sound. Small backyard home (ADU): A wooden deck with glass railings attached to a house in a forest Attached ADUAn addition sharing a wall with the house, with a separate entrance.

ADU design and permits

Survey review, deed restriction reading, flood elevation, plans, engineering and the city submittal.

How design and permits work

Which ADU type fits a Houston lot?

Start with paperwork, not the yard. If your recorded deed restrictions limit a lot to one residence, no layout fixes that. If they allow a garage apartment or servants' quarters, the wording tells you which type to build.

Next comes the ground. A lot in the 500-year floodplain must have its finished floor raised, which favors a garage apartment, where the living space already sits high, over a slab-level cottage. A sound existing garage on a dry lot points to a conversion.

How big can a second unit be inside Houston city limits?

As of October 2026, a lot keeps its single-family residential status under Chapter 42 with a second dwelling unit of up to 1,500 sq ft. The city raised that limit from 900 sq ft in rules that took effect November 27, 2023. The suburbs we serve set their own limits, often much lower.

How do the types compare?

  • Backyard cottage: new foundation, framing, roof and utility trench. Most flexible layout.
  • Garage apartment: two stories, so stairs, structure and height matter. Keeps parking.
  • Garage conversion: lowest structural scope when the garage is sound. Loses the parking.
  • Attached ADU: shares a wall and sometimes a roof with the house. May be classified differently from a detached unit, which we confirm.

As of October 2026, from City of Houston Planning & Development (Livable Places) and Chapter 19 floodplain rules. Suburban limits differ; see areas.

Check what your lot allows

Send your address. We tell you which of these types your restrictions, flood zone and city rules leave open.