St. Louis — City of St. Louis Mayor Tishaura Jones has signed legislation adopting the 2021 Uniform Plumbing Code (UPC), updating the city’s code from the 2009 edition of the UPC. The adoption was recommended by the city’s Committee of Plumbing Code Review and has the enthusiastic support of St. Louis’ plumbing industry.
Alderman Bret Narayan (Ward 24) sponsored Board Bill 182 and guided it through the adoption process. The legislation unanimously passed out of the St. Louis Health and Human Services Committee and moved forward to the Board of Aldermen for consideration, passing overwhelmingly on Feb. 3 and 7.
“I applaud the work of Alderman Narayan, the St. Louis Health and Human Services Committee and the Board of Aldermen in updating the city’s plumbing code from the 2009 UPC to the 2021 UPC,” said Brian Rogers, IAPMO senior vice president of Field Services. “This action helps ensure the residents of St. Louis have access to a newer code that reflects changes in water conservation and plumbing technology. The adoption of the 2021 UPC will benefit citizens throughout St. Louis and reaffirms the city’s commitment to help ensure that all buildings have safe and cost-effective plumbing systems that meet the demands of today’s consumers.”
One of the many significant updates found in the 2021 UPC is the addition of the Water Demand CalculatorTM (WDC). The UPC is the only national model plumbing code with significant updates for water pipe sizing in buildings since the development of Hunter’s Curve more than 80 years ago. It is the result of a multiyear, IAPMO-led effort to develop a new statistically based pipe sizing method stemming from a need to address profound water safety and wasted water and energy concerns due to oversized water supply pipes in homes and buildings.
Other noteworthy updates in the 2021 edition include:
“Updating the Uniform Plumbing Code as recommended by the city’s Committee of Plumbing Code Review ensures St. Louis residents have access to the most progressive, sustainable, and resilient plumbing code available,” Alderman Narayan said. “The adoption of the 2021 Uniform Plumbing Code is the highest level of health and safety protection and will benefit all citizens of St. Louis well into the future.” The UPC was introduced in Los Angeles in 1928 and formally published as the Uniform Plumbing Code in 1945. It is developed using IAPMO’s consensus development procedures accredited by the American National Standards Institute (ANSI). This process brings together volunteers representing a variety of viewpoints and interests to achieve consensus on construction practices. Developed and subsequently republished at the conclusion of each three-year code cycle, the Uniform Codes are designed to provide consumers with safely functioning systems while, at the same time, allowing latitude for innovation and new technologies.
IAPMO®, developer of the Uniform Solar, Hydronics and Geothermal Code (USHGC®) and Uniform Swimming Pool, Spa and Hot Tub Code (USPSHTC®), has posted online the 2025 Report on Proposals for the 2027 editions of these prospective American National Standard-designated model codes.
IAPMO® and the American Society of Plumbing Engineers (ASPE) have renewed a Memorandum of Understanding (MoU), now incorporating ASSE International and ARCSA International, to jointly advance and promote the mutual interests of education, regulations, design, specifications, installation, and inspection of plumbing systems, as well as training, testing and certifying qualified professionals to perform design work responsive to the need to conserve and protect water supplies, and reduce energy use connected to delivery and use of water.
IAPMO®, developer of the Uniform Plumbing Code (UPC®) and Uniform Mechanical Code (UMC®), has posted online the 2025 Report on Comments (ROC) for the 2027 editions of these American National Standard-designated model codes. The ROC includes the committee actions as discussed during the May 6-8 technical committee meetings, the electronic ballot results as balloted between May 19-June 16, and the Technical Correlating Committee actions on all comments received for the 2027 editions.