PRESS RELEASE

    IAPMO Releases Peak Water Demand Study: Full Study, Advancing Efficient Plumbing Design

    IAPMO Releases Peak Water Demand Study: Full Study, Advancing Efficient Plumbing Design

    Ontario, Calif. — IAPMO® has released Peak Water Demand Study: Full Study, a comprehensive analysis redefining water supply system sizing for residential and multi-family buildings. Based on real-world data from more than 1,000 households, the full study provides an evidence-based approach to right-sizing plumbing systems — demonstrating reductions in water waste, construction costs, and public health risks.

    A revolutionary tool, IAPMO’s Water Demand Calculator® accurately predicts peak water demand in single-family homes and multi-family buildings. Right-sizing of the piping system helps decrease construction costs, reducing the carbon footprint of the structure and saving consumers on both their water and water heating-related energy utility bills for the entire life of the plumbing system. At the same time, right-sizing has the potential to reduce the threat of bacterial growth within the system, which can lead to such serious health risks as Legionnaires’ disease.

    Key parts of the study include:

    • Results and recommendations for the end use of fixture and appliance flow rates.
    • Description of the fixture use probabilities that were observed as part of a more than 1,000-home data set.
    • Explanation of the algorithms used in calculating peak flow rates as part of the Water Demand Calculator.

    “By leveraging real-world data, this study not only proves that right-sizing plumbing systems can reduce water waste and construction costs, but it also plays a crucial role in enhancing public health and minimizing environmental impact,” said Dan Cole, senior director of Technical Services and Research. “We’re excited to offer the Water Demand Calculator as a revolutionary tool that will empower builders, designers and consumers to make smarter, more sustainable choices for the future.”

    IAPMO encourages plumbing professionals, regulators, and builders to adopt these findings. The study supports the expanded use of the Water Demand Calculator, already implemented in multiple states and jurisdictions.

    Access the full study at https://iapmo.org/research/whitepapers-and-studies/peak-water-demand-full-study.

    Report on Comments Toward Development of 2027 UPC, UMC Now Available for Online Download

    01 August 2025

    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.

    IAPMO® Supports APEC Workshop in South Korea on Safe Drinking Water

    31 July 2025

    IAPMO®, a global team of experts engaging industry and government for a safer built environment, was proud to support the the Asian-Pacific Economic Cooperation (APEC) Workshop: Strengthening Standards and Technical Regulations for Safer Drinking Water – Developing an International Roadmap. The two-day workshop helped kick off the Third Senior Officials’ Meeting and Related Meetings (SOM3), which began July 26 and are slated to run through Aug. 15.

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