After some negotiation, on November 7 the Alliance for Water Efficiency (AWE) and Plumbing Manufacturers International (PMI) came to an agreement and signed a Memorandum of Understanding (MOU) to deal with the issue of multiple showerheads in single shower stalls, particularly how the subject is treated in green stretch codes that stress water efficiency. AWE had been concerned that differing provisions were being considered at many green codes and standards venues: IAPMO’s Water Efficiency and Sanitation Standard (WE-Stand); ASHRAE’s Standard 189.1 Standard for the Design of High-Performance Green Buildings Except Low-Rise Residential Buildings; the U.S. Green Building Council’s Leadership in Energy and Environmental Design (LEED); the WaterSense® Homes specification; and other such forums. At issue was whether these green codes would potentially allow multiple showerheads that flow in excess of 2.0 gpm in shower compartments designed for only one person. The agreement reached between AWE and PMI will work to ensure water efficiency in green homes and buildings, and also work to provide harmonization of requirements in green codes and standards on this important issue.
The agreement limits the combined flows of multiple showerheads serving a one-person shower compartment to a maximum of 2.0 gpm, and stipulates that shower compartments designed for two persons be constructed using two separate shower valves which are installed no less than 96 inches apart measured horizontally, ensuring that such shower compartments are indeed designed for two people. Both organizations agree to support this provisions at all green code and standard venues.
Source: Alliance for Water Efficiency