Non-Rated Corridor in Partially Sprinklered Building

[m.nelson.arch.]

I’m working on an alteration to an existing building:

-2-story structure

-Type 1A construction, 3-hour rated structure and floor assemblies.

-Existing and planned uses: Higher Ed B-Use Group



The existing building does not have a sprinkler system.

Proposed work is limited to a second floor renovation.

Planned work includes a new sprinkler system, that while sized to serve the whole building, will only be installed at the second floor / area of work, with first floor sprinkler system being installed at a future date.



Is there a basis for permitting a non-rated corridor at the second floor?



While the code (1020.1) does not explicitly permit this condition, I believe that the intent of the code is met. Occupants of the first floor corridor are protected by rated enclosures and 3-hour separation from occupied space above; occupants of the second floor are protected by a fire suppression system and 3-hour rated floor/ceiling assembly below.



510.2 Gives credence to a 3-hour rated floor assembly having significance in the building code as a means of defining separate buildings when paired with a sprinkler system. While a sprinkler system below is not present, the floor assembly significantly elevates safety and separation between the floors.



Thoughts are appreciated.

 

[cda]

Welcome

Do you mind saying occupation ?

 

[cda]

I hate piecemeal,

Sounds like a set down with the ahj and draw up a plan,

Everyone ageees and have it written in stone for ever and ever

 

[steveray]

It's a good argument, but one you will have to have with the AHJ....The code says buildings sprinklered throughout get the corridor gimme....

 

[m.nelson.arch.]

CDA: Architect.

..a sit down with the AHJ is planned, I've spoken with them twice in the meantime. They've asked for further substantiation. I reached out to state oversight, awaiting response. Have also found precedent in NFPA 101 and a few City Building codes. Was opening it up to the group here for scatter-shot thoughts/opinions, all of which are appreciated.

Steveray: Thanks for the response.

 

[cda]

Yes I have seen deals cut where install does not meet code without something that will be done later.

I do not like them, but understand


You say 2nd floor will have sprinklers, so in away it meets code for non rated.

1. I take it 2nd floor will be occupied ??

2. What will be going on on the 1st floor while 2nd is in use??

 

[mtlogcabin]

The IEBC does not require a building to be sprinklered throughout the entire building. Only the work area needs to have fire protection.

2012 IEBC Level 3 alteration
904.1 Automatic sprinkler systems.
Automatic sprinkler systems shall be provided in all work areas when required by Section 804.2 or this section.

804.2.2 Groups A, B, E, F-1, H, I, M, R-1, R-2, R-4, S-1 and S-2.
In buildings with occupancies in Groups A, B, E, F-1, H, I, M, R-1, R-2, R-4, S-1 and S-2, work areas that have exits or corridors shared by more than one tenant or that have exits or corridors serving an occupant load greater than 30 shall be provided with automatic sprinkler protection where all of the following conditions occur:
1. The work area is required to be provided with automatic sprinkler protection in accordance with the International Building Code as applicable to new construction; and
2. The work area exceeds 50 percent of the floor area.

 

[m.nelson.arch.]

cda: Both floors will be occupied by a higher ed B-use. Generally offices and classrooms, student break-out space. 1020.1 requires a sprinkler system throughout rated corridors. While I think that there is sound code logic to say the second floor corridor is protected by the new sprinkler system, the first floor corridor remains protected by rated enclosures, there isn't a section of IBC that I can point to that corroborates.

mtlogcabin: Thank you very much. Will review in more detail, but I believe this section applies more to whether or not a sprinkler system is required for the planned work rather than whether or not sprinkler coverage can be used in lieu of corridor ratings.

In the case of this project, a sprinkler system isn't required for height or area reasons, or for IBC chapter 9 compliance, as the building is Type 1A construction, B-Use / Higher Ed. The sprinkler system is being added solely for the purpose of having non-rated corridors / the objective being to open up the floor visually, facilitate student interaction, etc. 1020.1 however doesn't explicitly permit this.

My choices seem to be to forget the sprinkler system and rate the corridors (a show-stopper) or seek a formal variation based on the logic outlined so far. The second option being my preferred course, but it's a rocky road getting there. Jammed between the usual rock/hard place, schedule constraints etc. Was optimistically looking for a more direct path to convey compliance to the AHJ.

Thanks again for the feedback.

 

[cda]

cda: Both floors will be occupied by a higher ed B-use. Generally offices and classrooms, student break-out space. 1020.1 requires a sprinkler system throughout rated corridors. While I think that there is sound code logic to say the second floor corridor is protected by the new sprinkler system, the first floor corridor remains protected by rated enclosures, there isn't a section of IBC that I can point to that corroborates.

mtlogcabin: Thank you very much. Will review in more detail, but I believe this section applies more to whether or not a sprinkler system is required for the planned work rather than whether or not sprinkler coverage can be used in lieu of corridor ratings.

In the case of this project, a sprinkler system isn't required for height or area reasons, or for IBC chapter 9 compliance, as the building is Type 1A construction, B-Use / Higher Ed. The sprinkler system is being added solely for the purpose of having non-rated corridors / the objective being to open up the floor visually, facilitate student interaction, etc. 1020.1 however doesn't explicitly permit this.

My choices seem to be to forget the sprinkler system and rate the corridors (a show-stopper) or seek a formal variation based on the logic outlined so far. The second option being my preferred course, but it's a rocky road getting there. Jammed between the usual rock/hard place, schedule constraints etc. Was optimistically looking for a more direct path to convey compliance to the AHJ.

Thanks again for the feedback.

Forgot,
What is the building used for now??? in use?

I think try to broker a deal that building will be eventually sprinkled.

it is only two floors, sprinkle the entire building now, it will more than likely save money, than doing it later.

 

[m.nelson.arch.]

Existing & Planned are both B-Use (Higher Ed Offices, Classrooms, etc.)

Trying to work up a feasible approach for adding sprinklers to the first floor but logistics are tough. Moving 25,000 SF of existing occupants into swing space, ancillary ceiling / lighting / HVAC cost, collateral damage to furniture, etc.

 

[cda]

So no change of occupancy

Indirectly you are making it safer.

I think have heart to heart and broker a deal to sprinkle the 1st floor later.
On the premise the building is not going to be more hazardous.

 

[m.nelson.arch.]

My thinking as well. I appreciate the feedback.

 

[mtlogcabin]

I forgot to include the final code section.
Basically the IEBC does not require a fire suppression system throughout the entire building Where a fire suppression system is installed through out the entire story with quick response heads since it is a Light Hazard Ocupancy
IBC TABLE 1018.1 CORRIDOR FIRE-RESISTANCE RATING would apply and a rated corridor is not required

2012 IEBC 804.1.1 Corridor ratings.
Where an approved automatic sprinkler system is installed throughout the story, the required fire-resistance rating for any corridor located on the story shall be permitted to be reduced in accordance with the International Building Code. In order to be considered for a corridor rating reduction, such system shall provide coverage for the stairwell landings serving the floor and the intermediate landings immediately below.

 

[JPohling]

California would typically require you to sprinkle the entire building to receive the rated corridor exception.