Increased Occupancy - Not Enough Plumbing Fixtures

[Young Architect]

Looking for a section in the IEBC that would allow me to increase the occupant load but not need to increase the number of plumbing fixtures. Egress capacity is still met, it is only plumbing fixtures that are the issue.

I want to add some conference rooms and a break area. The existing area is open office / private offices - not increasing the building sq/ft. When calculating the occupants for these new spaces and the existing to remain spaces for the remainder of the building (1 story office building) there is not have enough existing plumbing fixtures. The existing plumbing count does not appear to be enough for the existing space / occupant count. I am not certain how the plumbing calcs were originally run (last renovation in 2000).

The owner will not want to modify the restrooms.

Looking for some section of the code that will allow me to modify the existing offices / workspace to conference rooms / break area without needing to increase the plumbing counts. It is not a signification renovation of the building or even a majority of the sq/ft.

 

[classicT]

Presuming that you are looking at a Level 2 Alteration, you may use IEBC Section 810.1.

810.1 Minimum Fixtures
Where the occupant load of the story is increased by more than 20 percent, plumbing fixtures for the story shall be provided in quantities specified in the International Plumbing Code based on the increased occupant load.

 

[classicT]

However, if you fall under a change of use, see IEBC Section 1010.1, which is not so favorable to your request.

1010.1 Increased Demand
Where the occupancy of an existing building or part of an existing building is changed such that the new occupancy is subject to increased or different plumbing fixture requirements or to increased water supply requirements in accordance with the International Plumbing Code, the new occupancy shall comply with the intent of the respective International Plumbing Code provisions.

 

[classicT]

And sorry for the third post. But just noticed that you are new to the forum.

WELCOME!

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[mtlogcabin]

2018 IBC Changed the occupant load calculations. A "B" use is 150 sq ft per person or a concentrated occupant load of 50 sq ft per person.
I suggest you recalculate the OL based on the 150 sq ft [per person and see if that helps.

1004.8 Concentrated business use areas.
The occupant load factor for concentrated business use shall be applied to telephone call centers, trading floors, electronic data processing centers and similar business use areas with a higher density of occupants than would normally be expected in a typical business occupancy environment. Where approved by the building official, the occupant load for concentrated business use areas shall be the actual occupant load, but not less than one occupant per 50 square feet (4.65 m2) of gross occupiable floor space.

 

[Young Architect]

The 810.1 reference should help me. Thank you!

A follow up to this item... As I was researching the existing building's Type of Construction. I think it is most likely a type II-B classification (I still need to do some site investigation to confirm) From photos it is steel structure with no fire proofing. If I reference the allowable sq/ft under Type II-B construction, I realized that the existing building is over what is allowed in the current code (currently around 97,000sq/ft). Is there some exception I can reference for this particular issue? I am not adding any sq/ft... I am also trying to search through IBC if there is any exception to Type II-A construction where the primary structure would not need to be 1 hour rated... the building is equipped throughout with automatic sprinkler system.

This building was originally built in the 1980's. I am a little perplexed how to handle this situation. I am sure there is a way to make the planned alterations without needing to add fire proofing on the existing structure.

I originally mis-typed in my first post - this is a 2 story building.

Referencing IBC 2015

 

[ADAguy]

Oops, a DC project, review by federal architect. What code are they using and are the exist'g RRs ADA compliant?