Data sources: State plumbing boards, ICC, IAPMO, EPA Last verified: 2026-03-17

Plumbing Code

Arizona follows the Uniform Plumbing Code (2018 edition).

Plumbing codes are adopted and amended by local jurisdictions; check your city or county for the code in force

The UPC (Uniform Plumbing Code) is maintained by IAPMO (International Association of Plumbing and Mechanical Officials) and is primarily used in western states. It covers similar topics to the IPC with some differences in pipe sizing and fixture requirements.

Backflow Prevention Testing

Annual testing is required in Arizona for testable backflow prevention assemblies (RPZ, DCVA, PVB).

• Residential: May be required for homes with irrigation systems or other cross-connections; check local water-supplier rules
• Who can test: Certified tester
• Enforcement: Local water utility
• Note: Utility-enforced; commercial and irrigation

Water Heater Installation

A permit is required to replace or install a water heater in Arizona.

• Licensed plumber required: No - homeowner exemption available
• Homeowner can DIY: Yes, for primary residence (check local permit requirements)
• Note: Some cities allow homeowner pulls for primary residence

Universal requirements (all states):

• Temperature & Pressure Relief (TPR) valve must be installed
• Discharge pipe from TPR must terminate safely
• Gas water heaters: proper venting required
• Gas water heaters in garages: an 18" elevation of the ignition source above the floor may apply, subject to equipment exceptions and local code
• Expansion tank often required when backflow preventer is installed on main supply

Homeowner DIY Plumbing Rights

Arizona allows homeowners to perform plumbing work on their primary residence.

Varies by city; primary residence usually allowed

Water Conservation Requirements

Arizona follows federal water conservation minimums (no additional state mandates).

Federal minimums apply; drought areas may have stricter rules

Lead Service Line Replacement

Under the EPA Lead and Copper Rule Revisions (2021), water systems in Arizona must inventory service lines; the Lead and Copper Rule Improvements (2024) add requirements to replace lead service lines. Ask your water system for its inventory and replacement plan.

Important Disclaimer

This information is provided as a general overview. Plumbing codes and regulations can vary significantly between municipalities within Arizona. Always check with your local building department before starting any plumbing work. Local codes override state minimums - your city or county may have stricter requirements.

Sources

• State plumbing boards and licensing agencies
• International Code Council (ICC) - IPC adoption map
• International Association of Plumbing and Mechanical Officials (IAPMO) - UPC adoption
• Manual de control de conexiones cruzadas de la EPA (guía de la Ley de Agua Potable Segura)
• State building departments

Sources

• Arizona state plumbing board and licensing agency
• International Code Council (ICC) - IPC adoption map
• International Association of Plumbing and Mechanical Officials (IAPMO) - UPC adoption
• EPA Cross-Connection Control Manual (Safe Drinking Water Act guidance)
• State and local building departments