PRESS RELEASE

    IAPMO’s Water Demand Calculator™ Version 2.2 Available for Download

    IAPMO’s Water Demand Calculator™ Version 2.2 Available for Download

    The International Association of Plumbing and Mechanical Officials (IAPMO®) is excited to announce that the Water Demand Calculator™ version 2.2 is now available for download.

    While the basic template of version 2.1 of the calculator remains intact, version 2.2 includes several new features. First, version 2.2 implements a new algorithm called the method of convolution to replace exhaustive enumeration. The new algorithm is faster and has a smoother transition to the other methods of computation. This new computation method assures accurate predictions of peak indoor water demand.

    A second new feature of the Water Demand Calculator version 2.2 is the enhanced display showing the method of computation. After running the Water Demand Calculator, a new box in the computed results column shows the exact algorithm used in the calculation.

    A third new feature of version 2.2 is that the results of the peak flow calculation are now downloaded in a Microsoft Excel spreadsheet rather than a text file. The spreadsheet displays all the results and the list of fixtures and fixture counts entered into the calculation. In addition, an updated user guide is also available for version 2.2.

    “The Water Demand Calculator has become more robust while remaining fast, accurate and user-friendly,” said Dan Cole, IAPMO’s senior director of Technical Services. “Increasing the accuracy in predicting peak water demand for single- and multifamily dwellings will lead to reductions in pipe sizing accompanied by additional cost savings.”

    The Water Demand Calculator version 2.2 and user guide may be downloaded HERE. For specific information about the Water Demand Calculator or to provide feedback, please contact Dan Cole at dan.cole@iapmo.org.

    IAPMO Announces Publication of IAPMO/ANSI/CAN Z1403-2026, Water Demand Calculator

    14 October 2026

    IAPMO® is pleased to announce the publication of IAPMO/ANSI/CAN Z1403-2026, Water Demand Calculator®, a new American National Standard and National Standard of Canada that provides a modern, statistically based method for estimating peak water demand in single-family and multifamily residential buildings. 

    SCB Issues First AAC Certification Program Certificates

    08 October 2026

    IAPMO’s Systems Certification Body (SCB) has issued the first certificates under the Aluminum Anodizers Council (AAC) Certification Program, providing independent third-party verification of conformity with established performance requirements for anodized aluminum finishes and products.

    Shirley Dewi Promoted to Executive Vice President of IAPMO R&T

    05 October 2026

    IAPMO® is pleased to announce that Shirley Dewi has been promoted to executive vice president of IAPMO R&T, where she will provide strategic leadership and oversight for the organization’s certification and compliance operations, including Product Certification, the Systems Certification Body (SCB) and Continuous Compliance.

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