What building codes apply in Phoenix, Arizona?

A home built in Phoenix is checked against the 2024 Phoenix Building Construction Code (PBCC), which bundles the 2024 family of International Codes plus the 2023 National Electrical Code. The main code for a custom house is the 2024 International Residential Code (IRC). The City Council approved the package on June 18, 2025, by Ordinance G-7397, with an effective date of August 1, 2025. The city, not the state, enforces these codes inside city limits, and each model code carries Phoenix's own amendments.

Which codes Phoenix enforces

Phoenix enforces the 2024 I-codes for nearly everything and the 2023 electrical code, all bundled as the 2024 PBCC. Here is the working list for a single-family build:

• 2024 International Residential Code (IRC): one- and two-family homes and townhouses. This is the code a custom-home builder lives in day to day.
• 2024 International Building Code (IBC): larger and commercial structures.
• 2024 International Energy Conservation Code (IECC): insulation R-values, window U-factors, duct sealing, and HVAC efficiency.
• 2024 International Plumbing Code (IPC): water supply, drains, and fixtures. Phoenix also adopts the 2024 Uniform Plumbing Code (UPC) as an alternate path.
• 2024 International Mechanical Code (IMC): heating, cooling, and ventilation.
• 2024 International Fuel Gas Code (IFGC): gas piping and gas appliances.
• 2023 National Electrical Code (NEC): all wiring and electrical work.

The City of Phoenix is the authority having jurisdiction (AHJ) for these codes. That term means the body with legal power to adopt, amend, and enforce the rules. In Phoenix, that is the city building official, so the final word on your plans comes from city staff, not from Maricopa County or the state. For the full breakdown of editions, the ordinance, and where the amendments live, see our reference page on Phoenix's adopted building codes.

What an "adopted code edition" means for you

An adopted code edition is the specific year-version of a model code that a city has voted into law, and it sets the exact rules your house must meet. The International Code Council publishes new editions every three years (2018, 2021, 2024). A city does not automatically use the newest book. It votes to adopt a chosen edition, then enforces that one until it adopts a newer one. Phoenix adopted the 2024 cycle, so a 2024 rule controls your build.

This matters because editions differ in real, buildable ways. A 2018 energy code and a 2024 energy code can call for different insulation, different duct-leakage limits, and different window ratings. The 2023 NEC requires arc-fault and ground-fault protection in places older code books did not. If your designer copies a sheet from an older project, the numbers may not match Phoenix's 2024 requirements, and plan review will send it back with corrections before a permit issues.

Phoenix is direct about when the new code took over:

On June 18, 2025, the Phoenix City Council approved the adoption of the 2024 Phoenix Building Construction Code (PBCC). The City of Phoenix is transitioning to this updated code with an effective date of August 1, 2025.

So the rule you actually build to is the published 2024 edition as changed by Phoenix's amendment document for that code. Those local edits cover the things a desert city cares about most. They are short, but they control real choices on your plans. A few common areas they touch:

• Energy and heat. Phoenix edits the 2024 IECC for the local climate, which shapes your insulation, duct sealing, and efficiency paperwork.
• Plumbing path. Phoenix lets you build to either the 2024 IPC or the 2024 UPC, which is a real choice your plumber makes.
• Accessibility. The amended 2024 IBC references the ICC A117.1-2017 standard plus the 2010 ADA Standards.
• Administrative items. Permit fees, inspection steps, and submittal rules live in the amendments too.

The base book plus the amendment document together form the rule. Your designer reads them side by side, not one instead of the other.

Why Phoenix differs from its neighbors

Phoenix sits at the leading edge of the metro's code range, which spans the 2018 edition to the 2024 edition across nearby cities, and that gap is the single biggest reason a plan that passes in one city can fail in another. Each city adopts on its own schedule, so neighbors land on different editions:

• Scottsdale runs the 2021 I-codes and 2020 NEC, one cycle behind Phoenix.
• Cave Creek moved to the 2024 codes and 2023 NEC on January 1, 2026, though it keeps the 2018 residential energy code.
• Fountain Hills moved to the 2024 codes and 2023 NEC for permits filed on or after September 1, 2025.
• Carefree still runs the 2018 I-codes and 2017 NEC, two cycles behind Phoenix.
• Unincorporated Maricopa County (including Rio Verde Foothills) uses the 2018 I-codes and 2017 NEC.

That spread means a wiring plan drawn to the 2020 NEC for a Scottsdale lot is not automatically right for a Phoenix lot on the 2023 NEC, and a 2018 energy sheet from a county build will not meet Phoenix's 2024 energy code. The city line decides the code, not the metro. The fix is simple: design to the edition of the city where the lot actually sits.

How to confirm the current code with the city

Confirm the adopted edition directly with Phoenix Planning and Development before you finalize plans, because editions and amendments change. The city publishes its adopted codes, the ordinance, and the effective date on its Building Construction Codes page. Arizona's broader adoption picture, city by city, is tracked by the code authors at the ICC Code Adoptions map for Arizona.

Timing is the wrinkle in Phoenix right now. The prior code was the 2018 PBCC (Ordinance G-6463) with the 2017 NEC. Your code edition is tied to when the permit was issued, not today's calendar. If you pulled a permit before August 1, 2025, your project may still run under that 2018 edition. Anything new in Phoenix runs on the 2024 codes and the 2023 NEC. When you pull a permit, the office can confirm exactly which edition and which amendments apply to your address.

What a builder must design to

Give your designer, structural engineer, and trades one clear instruction: build to Phoenix's 2024 I-codes and the 2023 NEC, with the city amendments applied. That single sentence prevents the most common and most expensive plan-review correction, which is a sheet drawn to the wrong edition. In practice, that means the structural engineer details framing and foundations to the 2024 IRC, the energy consultant runs insulation and duct numbers to the 2024 IECC, and the electrician wires to the 2023 NEC.

When you compare contractor bids, confirm each one is quoting current-code work. Fixing a wall or a panel after a failed inspection costs far more than building it right the first time. Jematell Homes builds in Phoenix and designs every plan to the city's current adopted edition, so the codes are handled before a single footing is poured. For how these codes get checked at the counter, see Phoenix Residential Building Permit Requirements, and for the whole project arc, see the steps to building a custom home in Arizona.

How Jematell Homes helps

Permitting and code compliance are part of our full-service project management. We would rather answer your questions before you build than after, so get in touch any time.

Sources

• City of Phoenix Building Construction Codes
• ICC Code Adoptions for Arizona
• ICC: The International Codes (I-Codes), updated every three years