BOARD INTERPRETATION
MINIMUM SIZE OF THE DRAIN FOR A RESIDENTIAL SHOWER HAVING MULTIPLE SHOWER HEADS
(enacted 11-27-2013)


1.   Introduction

The Board of State Examiners of Plumbers and Gas Fitters (“Board”) has voted to interpret 248 CMR, 10.10 (7) (b) Shower Waste Outlet

2.   Interpretation

To allow a maximum of five (5) shower heads to operate simultaneously utilizing one (1) 2” shower drain.

3.   Rationale     

While sizing the drain, a shower valve with one (1) head would be rated at two (2) fixture units, and each additional shower head added which could operate at the same time would be rated at one (1) fixture unit. This would allow a maximum of five (5) shower heads installed to operate simultaneously while utilizing a 2” drain.