What building codes apply in Fountain Hills, Arizona?

A home built in the Town of Fountain Hills is checked against 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), used here with Appendix G. The editions apply to permit applications received on or after September 1, 2025, adopted by the Town Council in Ordinance 25-06. One cost item stands out: Fountain Hills requires fire sprinklers in new homes. The Town, not the county or the state, enforces these codes inside town limits.

Which codes Fountain Hills enforces

Fountain Hills enforces the 2024 I-codes for nearly everything and the 2023 electrical code. Here is the working list the Town's Building Safety Division enforces:

• 2024 International Residential Code (IRC), with Appendix G: 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 Mechanical Code (IMC): heating, cooling, and ventilation.
• 2024 International Plumbing Code (IPC): water supply, drains, and fixtures.
• 2024 International Fuel Gas Code (IFGC): gas piping and gas appliances.
• 2024 International Energy Conservation Code (IECC): insulation R-values, window U-factors, and HVAC efficiency.
• 2024 International Fire Code (IFC): fire and life-safety provisions.
• 2024 International Swimming Pool and Spa Code (ISPSC): pools and spas.
• 2023 National Electrical Code (NEC): all wiring and electrical work.

The Town of Fountain Hills is the authority having jurisdiction (AHJ) for these codes. That term means the body with legal power to adopt, amend, and enforce the rules. Here, that is the Town Building Official, so the final word on your plans comes from Town staff. For the full breakdown of editions, the ordinance, and the amendments, see our reference page on Fountain Hills' 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 town 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 town does not automatically use the newest book. It votes to adopt an edition, then enforces that one until it adopts a newer one. Fountain Hills moved to the 2024 cycle in 2025, 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 Fountain Hills' 2024 requirements, and plan review will send it back with corrections before a permit issues.

The codified Town Code states the adoption plainly. Article 7-1 adopts each publication by reference:

The following listed publications, three copies of which are on file in the office of the Town Clerk and which are available for public inspection during normal business hours, are hereby adopted by reference, together with all appendices and supplements thereto.

The Town then adds its own 2024 Fountain Hills Amendments to the IBC, IRC, IECC, ISPSC, and IFC. Local amendments are the Town's own edits, covering desert and hillside items like grading, drainage, and fire access. So the rule you build to is the published 2024 edition as changed by those amendments. One older piece stays in: the Town's residential sprinkler rule cross-references the 2006 Fire Code as amended, which it adopted in 2008, so that single rule is older than the rest of the stack.

Why a sprinkler rule and neighbor differences matter

Fountain Hills carries a residential fire-sprinkler requirement that most metro cities do not, and it adds a real cost line to a new home here. The Town's amendments require sprinklers across new occupancies, so a custom home almost always needs a system. That changes your mechanical and water budget from the start. Plan for it in the first design meeting, not after the plans are drawn.

Fountain Hills also sits near the leading edge of the metro's code range, which spans the 2018 edition to the 2024 edition across nearby areas. Each city adopts on its own schedule, so neighbors land on different editions:

• Scottsdale, the closest large city, runs the 2021 I-codes and 2020 NEC, one cycle behind Fountain Hills.
• Phoenix runs the 2024 I-codes and 2023 NEC, effective August 1, 2025.
• Cave Creek moved to the 2024 codes and 2023 NEC on January 1, 2026, but keeps the 2018 residential energy code.
• Carefree runs the 2018 I-codes and 2017 NEC, two cycles behind.
• Unincorporated Maricopa County uses the 2018 I-codes and 2017 NEC, with no sprinkler mandate.

That spread means a set drawn for a 2018-code area is not automatically right for a Fountain Hills town lot, and the sprinkler rule alone can change your budget. The town line decides the code, not the metro.

How to confirm the current code with the Town

Confirm the adopted edition directly with the Fountain Hills Building Safety Division before you finalize plans, because editions and amendments change. The Town publishes its adopted codes, editions, and effective date on its Adopted Codes page. The adopting ordinance text and the per-code amendments live in the codified Town Code Chapter 7, which Ordinance 25-06 repealed and replaced. Arizona's broader adoption picture is tracked by the code authors at the ICC Code Adoptions map for Arizona.

Timing is the wrinkle here. Your code edition is tied to when your application is received, not today's calendar. A package filed before September 1, 2025 may still run under the prior code. Anything filed on or after that date runs on the 2024 codes and the 2023 NEC. When you apply, the office can confirm exactly which editions and amendments apply to your address.

What a builder must design to

Give your designer, structural engineer, and trades one clear instruction: build to Fountain Hills' 2024 I-codes and the 2023 NEC, with the Town's amendments applied, and plan for a residential fire-sprinkler system. That single sentence prevents the most common and most expensive plan-review correction, which is a sheet drawn to the wrong edition or to a neighboring jurisdiction's code. In practice, the structural engineer details framing to the 2024 IRC with Appendix G, the energy consultant runs numbers to the 2024 IECC, the electrician wires to the 2023 NEC, and the plans include the sprinkler design.

When you compare contractor bids, confirm each one is quoting current-code work and the sprinkler system, because a bid that leaves it out is not comparable. Fixing a wall or a panel after a failed inspection costs far more than building it right the first time. Jematell Homes builds in Fountain Hills and designs every plan to the town's current adopted editions, so the codes and the sprinkler rule are handled before a single footing is poured. For how these codes get checked at the counter, see Fountain Hills Residential Building Permit Requirements, and for the whole project arc, see the steps to building a custom home in Arizona.

How Jematell Homes helps

We handle jurisdiction, submittals, and inspections as part of every build. If you are planning a custom home in Scottsdale, Rio Verde, or the greater Phoenix metro, we are happy to walk through your project.

Sources

• Town of Fountain Hills Adopted Codes
• Fountain Hills Town Code Chapter 7: Buildings and Building Regulations (Ordinance 25-06)
• ICC Code Adoptions for Arizona