If memory serves, the IBC Chapter 29 and the related Plumbing Code (2015) both state the occupant load for determining plumbing fixtures is directly based on Chapter 10 occupancy. IBC 2902.1 states the count is based on the actual use of the spaces and not the entire building as a single use group.
IBC 2902.1.1 provides the 50/50 ratio although an exception exists if statistical data indicates a distribution differing from 50/50.
The clause allowing a lower fixture count when approved by the building official has been eliminated.
My advise is to read Chapter 10 on area per occupant closely, review a commentary and take advantage of the "net" versus "gross" on a room by room basis.
------------------------------
Audie Bates AIA
Senior Architect
The JDI Group, Inc.
Monroe MI
------------------------------
Original Message:
Sent: 04-22-2017 19:49
From: Thomas Fallon
Subject: Fixture count
The IBC uses Chapter 10 to determine the number of occupants. Someone else in here mentions this and of course you divide by 2 so that you have 50% men and 50% women. What I want to point out is that you may end up with a lot more occupants using this method, BUT the corresponding number of people being served by each fixture also changes in the IBC table. I have not done a thorough comparison but I do work in various jurisdictions throughout the country and have to switch depending on what the code is and have not noticed a difference (or at least not a noticeable difference) in the number of fixtures I am providing. When I first came upon this change I did take a look at that the difference for that project and it did not affect the outcome of the number of fixtures on THAT project.
------------------------------
Thomas Fallon AIA
Benner Stange Associates Architects, Inc.
Portland OR
------------------------------
Original Message:
Sent: 04-18-2017 20:31
From: Mary Myers
Subject: Fixture count
Code Calculation Question:
We have a tenant improvement project in Plano, Texas (33,363 SF). We are trying to do the fixture calculation per the International Plumbing Code. Does anyone have any experience doing this calculation for Texas per IBC 2015? In California we typically use a load factor of 200 (Found in Table A) to determine the occupant count and then divide by two. This helps reduce the number of fixtures required. I am not seeing this 200 load calculation option for IBC. Can anyone comment/confirm?
Thanks!
Kitty Myers AIA CSI CCS LEED AP
RMW architecture & interiors
160 Pine Street
San Francisco, CA 94111
Tel 415.781.9800 x719 Dir 415.490.1719
kmyers@rmw.com www.rmw.com
