Right-Sizing Water Distribution Pipes and Water Heating Systems to Save Energy and Reduce Building Costs

2050 Partners

Project Goals

1. Validate the Peak Water Demand Calculator (WDC) for water supply pipe sizing in Minnesota multifamily buildings.
2. Estimate potential water, energy, cost, and carbon savings from the use of the WDC.
3. Inform a code change proposal to start the adoption of UPC Appendix M into the Minnesota Plumbing Code (MPC).
4. Evaluate water heater sizing guidance to avoid costly oversizing of heat pump water heaters (HPWHs).

WDC design flow rates are 2 to 6 times larger than the observed peak flow rate for the four Minnesota buildings analyzed in this project. The traditional method overestimated peak flow by up to 25x, leading to oversized pipes. This is consistent with other out of state buildings previously analyzed.

Access the project article and project factsheet to start to take in this project’s background, key findings, and recommendations today. Register below for the webinar to learn more and engage with the principal researchers on this project.

Residential Multifamily Sector (5+ units) Date: Tuesday, October 14, 2025, 11a.m. to 12 noon CT Webinar Registration: https://minnesota.webex.com/weblink/register/ rbcbaba6f0a3a087095a36f858362f7ab

Conservation Applied Research and Development (CARD) projects aim to uncover new technologies and strategies to maximize energy savings, enhance energy conservation programs, and document CO2 reductions. The results from CARD research provide utilities with timely information to improve energy-efficiency program designs within their Energy Conservation and Optimization (ECO) portfolios. Many previous CARD webinars can be viewed HERE.