ARTICLE: Right-sizing Water Distribution Pipes and Water Heating Systems
Results
- The Peak Water Demand Calculator (WDC) used to size water pipes resulted in lower construction costs and operational cost savings.
- The WDC also led to faster delivery of hot water to unit occupants.
- Faster and more efficient hot water delivery reduced water and energy waste in the buildings studied, which in turn lowered carbon emissions and improved water quality.
Highlights
Objectives
Investigate opportunities to reduce energy use and construction costs in new residential multifamily buildings via best practices for right-sizing water distribution pipes and water heating systems
Scope
Evaluated the WDC from the 2024 Uniform Plumbing Code (UPC) Appendix M, comparing its performance against the traditional water supply pipe-sizing method in four Minnesota multifamily buildings.
Benefits
Results showed that the WDC method consistently designed for water demand flow rates much closer to actual usage than the traditional method, which overestimated flow rates by up to 25 times.
This article summarizes a CARD project to study water supply pipe and end use sizing to investigate opportunities to reduce energy use and construction costs in new residential buildings. The project team evaluated the peak water demand calculator (WDC) from the 2024 Uniform Plumbing Code (UPC) Appendix M to compare its performance against the traditional water supply pipe-sizing method in four Minnesota multifamily buildings.
Results from the study showed that the WDC method designed for water demand flow rates much closer to actual usage than the traditional method, which overestimated flow rates by up to 25 times. Based on their findings, the team made several recommendations to ensure the successful implementation of the UPC Appendix M, including launching education and outreach for plumbing and building industry professionals, considering incentive programs to bundle WDC demand sizing measure with heat pump water heater installations, and more.
This project is led by 2050 Partners and supported by a grant from the Minnesota Department of Commerce, Division of Energy Resources, through the Conservation Applied Research and Development (CARD) program.