FACTSHEET: Right-sizing Water Distribution Pipes and Water Heating Systems

This factsheet summarizes the project goals and key findings of this CARD-funded project seeking to validate and apply the peak water demand calculator (WDC) for water supply pipe sizing in Minnesota multifamily buildings and support the adoption of the UPC Appendix M into the Minnesota plumbing code. The team found that traditional methods overestimated peak water flow by up to 25 times as much, leading to significantly oversized pipes, while design flow rates calculated from the WDC were only 2–6 times larger than the observed peak flow rate. If the WDC is used in place of the standard practice design in 30% of new multifamily buildings, it would save the State of Minnesota an estimated 1.4 million gallons of water and prevent 141 metric tons of CO2e carbon emissions each year.

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.