What combination of WaterSense showerheads will achieve Water Efficiency Credit, Indoor Water Use?

LEED v4 Homes WE Credit “Indoor Water Use,” Path 2, awards credit when every showerhead installed is EPA WaterSense-labeled. The WaterSense Showerhead Specification (v1.1) limits flow to
• ≤ 2.0 gpm (7.6 L/min) at 80 psi, and
• ≤ 2.2 gpm (8.3 L/min) at 45 psi. For stalls with more than one operating outlet, the combined flow may not exceed 2.0 gpm at 80 psi.
Option A uses one head per stall rated 2.2 gpm at 45 psi and 1.6 gpm for the others; all individual heads satisfy WaterSense limits and no stall exceeds 2.0 gpm at 80 psi, so the project qualifies for the credit.

B. 2.5 gpm exceeds the 2.2 gpm (45 psi) WaterSense limit—cannot be WaterSense-labeled.
C. Two 2.0 gpm heads in one stall give 4.0 gpm combined, violating the 2.0 gpm/stall WaterSense cap.
D. 3.0 gpm head far exceeds WaterSense maximum flow; fails label requirement.

1. U.S. EPA. “WaterSense Specification for Showerheads, Version 1.1,” §3.0 Performance Criteria, pp. 3-4 (2010).

2. U.S. GBC. “LEED v4 Homes and Multifamily Lowrise Reference Guide,” WE Credit: Indoor Water Use, Path 2 – WaterSense Fixtures, p. 408-409 (2014).