Phoenix, AZ — The city of Phoenix has announced adoption of the 2024 Phoenix Building Construction Code, which incorporates the 2024 edition of IAPMO’s Uniform Plumbing Code (UPC®) and its Appendix M: the Water Demand Calculator — a breakthrough tool for modern plumbing design.
Implementation of the new code will begin Aug. 1, giving industry professionals time to prepare for the transition and align their practices with the latest safety and sustainability standards.
“The Uniform Plumbing Code and the Water Demand Calculator empower plumbing professionals to design right-sized systems that reduce construction costs, conserve water, and deliver hot water more efficiently,” said IAPMO CEO Dave Viola. “We applaud Phoenix for taking this important step toward building a more resilient, equitable, and sustainable city.”
Matthew Miles, P.E., with the city of Phoenix, added, “Adopting the 2024 Uniform Plumbing Code helps ensure industry professionals in Phoenix can rely on a clear, consistent, and modern set of requirements that support safety and constructability.”
The Water Demand Calculator, now codified in Appendix M of the UPC, uses statistical modeling of real-world water use to accurately predict peak demand for residential buildings. This innovation allows for dramatically smaller pipe diameters without compromising performance — improving energy efficiency, water quality, and cost savings over the life of the system.
Key benefits of Phoenix’s adoption of the 2024 UPC and Water Demand Calculator include:
- Improved Affordability: Right-sizing plumbing systems significantly lowers material and installation costs.
- Enhanced Water Efficiency: Reduces water aging and accelerates hot water delivery, improving user experience and hygiene.
- Decarbonization Support: Smaller systems reduce hot water energy use, aiding the city’s climate goals.
- Better Design Precision: Brings science-based sizing into plumbing practice, replacing outdated assumptions. The 2024 UPC is developed through a rigorous ANSI-accredited consensus process that includes public health officials, industry professionals, engineers, and code officials. It provides the most comprehensive, science-driven guidance for safe and efficient plumbing system design, installation, and maintenance.
