Height limits in Phoenix, AZ
Building codes decide when you need a permit; zoning decides how tall you can go. Both are below, measured the way Phoenix measures them.
Rules last checked by a person on October 19, 2026. Guidance only; confirm with Phoenix before you build.
Citywide
| ADU: Detached ADU height | 15 ft (a use permit can allow more) |
|---|
Check your lot
Sources
- Phoenix Building Construction Code 2024, Chapter 1 amendments (Sec. 105.2, effective 8/1/2025). Checked 2026-10-20.
One-story detached accessory structures used as tool and storage sheds, playhouses, non-cantilevered shade structures... floor area is not greater than... 200 square feet, except for unaltered Intermodal Shipping Containers not greater than 320 square feet.…
- 44 CFR 59.1, definition of development (NFIP). Checked 2026-10-19.
Development means any man-made change to improved or unimproved real estate, including but not limited to buildings or other structures...
- 44 CFR 60.3, floodplain management criteria. Checked 2026-10-19.
Require permits for all proposed construction or other development in the community...
- 2024 IRC R105.2, Work exempt from permit (text published by the City of Benson, AZ). Checked 2026-10-19.
One-story detached accessory structures, provided that the floor area does not exceed 200 square feet. Fences not over 7 feet high. Decks not exceeding 200 square feet in area, that are not more than 30 inches above grade at any point, are not attached to a…
- Phoenix TRT/DOC/00192, ADU Residential Process (Jan 2024). Checked 2026-10-19.
Must have site planning approval prior to moving on to residential submittal.
- City of Phoenix, Beginner's Guide to ADUs. Checked 2026-10-19.
Two ADUs are permitted per single-family detached lot... A detached ADU may be located within the required rear yard and may not exceed 15 feet in height... no closer than 5 feet to a street side property line; 3 feet from an interior property line, and 0 f…