SOUPER-CONFÉRENCE 20 OCTOBRE 2026

La conférence se déroulera en anglais

« The Water Demand Calculator: Transforming Plumbing System Design Through Data-Driven Pipe Sizing »

For decades, plumbing systems have been sized using fixture unit methods developed from assumptions about water use patterns that no longer reflect how modern buildings operate. The Water Demand Calculator, developed through research led by IAPMO and industry partners, represents a fundamental shift toward data-driven plumbing design by using real-world occupancy and fixture usage patterns to accurately predict peak water demand. This presentation introduces the research behind the Water Demand Calculator and explains why it is being adopted as a new approach to plumbing system sizing. Attendees will explore how right-sized piping systems can reduce construction costs, improve energy efficiency, decrease water age, and support better building water quality outcomes. Special emphasis will be placed on multifamily buildings, where traditional sizing methods often result in oversized piping systems and where the benefits of the Water Demand Calculator are most significant. The session will also discuss ongoing efforts to expand demand modeling to additional commercial building types and what this may mean for the future of plumbing engineering.

Learning Objectives

Upon completion of this session, participants will be able to: 

• Describe the research and development of the Water Demand Calculator and understand why modern water use patterns differ from the assumptions behind traditional fixture unit sizing methods.
• Identify the economic, operational, and water quality benefits of right-sized plumbing systems, including reduced material costs, lower energy consumption, and decreased water stagnation.
• Explain how the Water Demand Calculator estimates peak demand in multifamily buildings and how the methodology compares to conventional pipe sizing approaches.
• Evaluate real-world project examples demonstrating the impact of Water Demand Calculator-based designs on pipe sizing, infrastructure requirements, and building performance.
• Discuss the future evolution of demand modeling for commercial occupancies and understand opportunities for building owners, developers, and engineering firms to participate in next-generation research efforts.

Conférencier

Christoph Lohr, PE, CPD, ASSE 12080, LEED AP BD+C

Results-Oriented Expertise. Focused Leadership. Respected Energy. Christoph Lohr is IAPMO’s Vice President of Technical Services and Research. As part of his duties, he provides a systems-based approach to departmental leadership and strategy development, represents the organization in numerous committees and speaking engagements, and provides technical support to all IAPMO’s business units. Christoph has almost two decades of engineering experience especially in designing plumbing systems and has a reputation as a results-oriented expert, particularly in the realm of balancing waterborne pathogen prevention and water sustainability. He leads pioneering research efforts in plumbing science and water systems, helping to shape the next generation of evidence-based standards and design practices. He is a distinguished graduate from the Virginia Military Institute, with a Bachelor of Science in Mechanical Engineering.