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B occupancy - Fire rated corridor exception for automatic sprinkler system?

JPohling

SAWHORSE
Joined
Aug 16, 2011
Messages
1,692
Location
San Diego
2019 CBC

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2022 CBC

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OK this is a massive change or a massive error.

If you look at the 2019 table a B occupancy in a fire sprinklered building was given an exception for fire rated corridors if per footnote "c" the fire sprinkler system complied with 903.3.1.1 or 903.3.1.2. My understanding was that in order to take this exception the building would need to have been constructed after 1996. Buildings constructed before that date the fire sprinkler system would not comply with 903 and the exception could not be taken. This seemed reasonable as there were many changes to the fire sprinkler installation requirements in the 1996 edition of NFPA 13. I have been constantly battling with brokers who insisted that they could remove and derate all rated corridors and install glass doors and glazing throughout just because they were fire sprinklered.

Now I look at the 2022 CBC table 1020.2 and see that the footnote "c" has been removed from the top "with sprinkler system" notation and placed further down the chart at each occupancy. B occupancy now indicates a "0" rating if protected with a sprinkler system.............................. with no caveat regarding compliance with 903!

looking at the IBC 2015, it was consistent with the 2019 CBC chart. 2018 IBC is now consistent with the 2022 CBC as well

Is this a massive change or an error? any vintage fire sprinkler system will now provide a rated corridor exception?
What do you fine people think?
 

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Since they didn't correct it in the 2024 supplemental changes, I would assume it's intentional and not a mistake. Especially since they fixed the footnote errors that the original 2022 code had in this table.
 
Since they didn't correct it in the 2024 supplemental changes, I would assume it's intentional and not a mistake. Especially since they fixed the footnote errors that the original 2022 code had in this table.
That seems to be true that it is intentional. But there must be a mechanism to preclude owners of very old buildings that have sprinkler systems but were previously constructed with one hour corridors from simply removing the rated corridors or modifying them with glass doors, windows, non rated doors etc. thereby eliminating the one hour corridors due to the fact that they have a fire sprinkler system of any vintage. That is preposterous. Previously the fire sprinkler system needed to be installed after a certain date to allow taking the exception. San Diego jurisdiction it was 1996

I am not really well versed in the Existing Building Code but there is this. but this seems to address current installations not existing.
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That seems to be true that it is intentional. But there must be a mechanism to preclude owners of very old buildings that have sprinkler systems but were previously constructed with one hour corridors from simply removing the rated corridors or modifying them with glass doors, windows, non rated doors etc. thereby eliminating the one hour corridors due to the fact that they have a fire sprinkler system of any vintage. That is preposterous. Previously the fire sprinkler system needed to be installed after a certain date to allow taking the exception. San Diego jurisdiction it was 1996

I am not really well versed in the Existing Building Code but there is this. but this seems to address current installations not existing.
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Well that's new. I wasn't aware that the SFM adopted ch8 of the CEBC. Up until July 2024, Ch6 - Ch13 weren't applicable to California. I'm a bit surprised we're suddenly changing this.

Regardless, I too am unfamiliar with most of the CEBC, but I agree that 803.2 seems to address new installations instead of existing installations.
 
Back in the day all the buildings that were fully fire sprinklered still were required to provide rated corridors if they served more than 30 occupants. Then in the 2013 CBC the exception appeared to allow an exception to the corridor fire rating if the fire sprinkler system was installed per 903. essentially requiring sprinkler system compliance with NFPA 13 at that date. Now it seems that the requirement to comply with 903 has been removed except for H,L, I-3 and R2.1 occupancies. I really do not think that is correct. and I am missing something.................
 
I checked the 2018 Group A proposed changes and could not find where this change was proposed. My best guess is that it was changed during the review within the ICC Code Correlation Committee. They saw that Group R had used the "c" footnote for the half-hour rating and decided that all the other ratings should use the "c" footnote to be consistent. They deleted the footnote in the column heading because, in their mind, it became superfluous, not realizing what they had done by not placing the "c" footnote next to the 0-hour ratings.

My question is: Why did California decide to do away with 0-hour corridors in sprinklered Groups I-2 and I-2.1 when footnote "a" essentially supersedes the 1-hour rating? Also, they only put the "a" by Group I-2 and not Group I-2.1, when footnote "a" specifically includes both occupancy groups. Go figure.
 
Also, they only put the "a" by Group I-2 and not Group I-2.1, when footnote "a" specifically includes both occupancy groups. Go figure.
CA corrected this with the 2024 supplemental changes (effective July 2024). That one actually seemed to be a mistake in the base 2022 code. I-2.1 is soon to be deleted from code and the footnote has been corrected. They also edited 1020.2, exception 6. Can't keep anything too simple.
 
I don't know about California, but IBC 903.3.2 requires quick-response sprinklers in light-hazard sprinkler systems. Conventional sprinkler heads throughout an existing building would have to be replaced with QR heads to be able to convert a rated corridor to an unrated one.
 
I don't know about California, but IBC 903.3.2 requires quick-response sprinklers in light-hazard sprinkler systems. Conventional sprinkler heads throughout an existing building would have to be replaced with QR heads to be able to convert a rated corridor to an unrated one.
In addition to the quick response heads they would also need to address seismic braces, flexible couplings and pipe clearances as well. The problem is there does not seem to be any reference to 903 for a B occupancy any longer in table 1020.2. that is my concern
 
How do you Building Officials determine if an existing building equipped with automatic fire sprinklers is eligible to take the exception to 1 Hour fire rated corridors for a "B" occupancy from Table 1020.2?
 
Not sure why there are no responses from any Building Officials? this is a pretty critical change. Will you be allowing all of the existing fire rated corridors in your fire sprinkled non upgraded buildings from the 60's to be removed based upon this?
 
but IBC 903.3.2 requires quick-response sprinklers in light-hazard sprinkler systems. Conventional sprinkler heads throughout an existing building would have to be replaced with QR heads to be able to convert a rated corridor to an unrated one.
Meet the above

Will you be allowing all of the existing fire rated corridors in your fire sprinkled non upgraded buildings from the 60's to be removed based upon this?
NO. Quick Response and/or Residential sprinkler heads did not exist in the 60's.

Effective in CA on 7-01-2024
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MT, The issue is that if you look at the current code the requirement for compliance with 903 in order to take the corridor exception has been removed. Refer to table 1020.2 and footnote "c". it has been removed from the "with fire sprinkler" box to now being called out for each occupancy. No longer required except for H, L, I-3 & R2.1 only.
 
I was on the fire side from 1984 till 2021.

Yes technology of sprinklers has changed over the years.

As far as design, most I saw were hydraulically designed.

Early on I saw a few pipe schedule systems, that were either in place, or added on to. But, very few.

I would say as long as maintained, they should work.

As far as quick response sprinklers, yes they activate slightly faster, and may cause less sprinklers to activate.

I saw fire sprinkler systems work that were many years old.

I think it goes back to, the person wanting to go to non rated corridors, has to submit, why they were rated in the first place, and justification to allow them to be non rated now.

We did an old school with rated corridors, that was adding on, my boss the Fir Marshal, required rated corridors to remain in place, and go back and fix all the holes in the rated walls.
 
Here is an answer to my question by someone much more qualified than myself:

"I have looked into this now, including a review of the 2013 Code requirements and the 2022 Code requirements, and I don’t see where this really changes anything. And here is why I have reached that conclusion.



First, even back in the 2013 Code, the footnote was not a reference to CBC Section 903 in general, but instead a reference that took you to CBC 903.3.1.1 or 903.3.1.2. Those two sections are the requirement to provide a system that is compliant with NFPA 13 or NFPA 13R, respectively. I am not sure why that kind of a reference would be necessary except to clarify that when a building is eligible for an NFPA 13R system, it can be used to justify compliance with the fire sprinkler requirements of CBC Table 1018.1/1020.2.



Then, when you look at the current table, CBC Table 1020.2, the requirement to provide fire sprinkler protection has not gone away when a non-rated corridor is provided, only the footnote that directed you to an NFPA 13 or 13R system has been removed. So if the non-rated corridor option is proposed, the building must still be provided with fire sprinkler protection, and per CBC 903.1, that fire sprinkler protection must be compliant with Section 903, which would include compliance with 903.3.1.1 or 903.3.1.2 or 903.3.1.3, whichever is applicable. What needs to be kept in mind is that both NFPA 13D (903.3.1.3) and 13R (903.3.1.2) have scoping statements that define the types of occupancies and uses where the systems can be used, so the Standards themselves take some of the guesswork out of it. And if you cannot use the 13D or 13R Standards, then you have to use the 13 Standard. And that all brings you back to where we where before they relocated the footnote.



So based on this, I don’t see that anything has really changed, and it would be my conclusion that we will still enforce the same requirements that we have been enforcing."
 
The I-Codes over the years reduced the fire rated construction requirements if a fire suppression system was installed. This was done so designers would be able to encourage developers to install a suppression system by offsetting the savings on the fire rated assemblies that would be required for their project.

If the existing fire suppression system was not designed to meet 903.3 requirements then it is not an approved system under todays code that can be used for reduced fire rated hourly assemblies or increases in area or stories of buildings.

[F] 903.3 Installation requirements.
Automatic sprinkler systems shall be designed and installed in accordance with Sections 903.3.1 through 903.3.8.

Fire Code
701.2 Fire-Resistance-Rated Construction

Assembly
Diagram
The fire-resistance rating of the following fire-resistance-rated construction shall be maintained:
  1. Structural members.
  2. Exterior walls.
  3. Fire walls, fire barriers, fire partitions.
  4. Horizontal assemblies.
  5. Shaft enclosures.

Ca Existing Building Code
501.2 Fire-Resistance Ratings


Where approved by the code official, in buildings where an automatic sprinkler system installed in accordance with Section 903.3.1.1 or 903.3.1.2 of the California Building Code has been added, and the building is now sprinklered throughout, the required fire-resistance ratings of building elements and materials shall be permitted to meet the requirements of the current building code. The building is required to meet the other applicable requirements of the California Building Code.
Plans, investigation and evaluation reports, and other data shall be submitted indicating which building elements and materials the applicant is requesting the code official to review and approve for determination of applying the current building code fire-resistance ratings. Any special construction features, including fire-resistance-rated assemblies and smoke-resistive assemblies, conditions of occupancy, means of egress conditions, fire code deficiencies, approved modifications or approved alternative materials, design and methods of construction, and equipment applying to the building that impact required fire-resistance ratings shall be identified in the evaluation reports submitted.
 

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The I-Codes have also been amended over the years to push people into sprinklering buildings by adding expensive requirements such as smoke dampers and smoke gasketing in corridors that require a fire rating. The agency I worked for before retiring started sprinklering college classroom buildings so that it wouldn't be too difficult to reconfigure them in the future, even though there had only been 2 fires that caused significant damage, and no casualties that I am aware of, in 23 colleges over the last 50 years.
 
I was on the fire side from 1984 till 2021.
@cda couldn't stay away!! Always good to know that you're still watching out for us. It's much appreciated!
How do you Building Officials determine if
Not sure why there are no responses from any Building Officials?
I'd be willing to bet that most Building Officials who frequent this site would not want to have to make a call like this unless they're faced with making that determination in their own jurisdiction. I am getting the feeling (more and more lately) that people on the other side of the counter think that the code is a clear roadmap that we've all agreed upon. Couldn't be further from the truth. The job of a BO is to read and interpret the code. They have the duty to then apply the code (as they interpret it) to the practical real-life scenarios they face. The reality is that each building official in has the authority to make those calls in their jurisdiction, and they're not always going to agree.

This forum is very interesting in this respect, it seems to mirror the reality we face at work on a day-to-day basis. The frequent users are a mix from both sides of the counter and are willing to engage and debate the nuances of the code. Then occasionally you get someone fishing for the answer they want and get mad when they don't get it. Sum's up a usual day around my office....
 
Many years ago I remember a UBC instructors egress portion of his class dealing with corridors and the purpose behind the code requirements for corridor construction.

Not verbatim but what I can remember.

A corridor acts and functions the same as a cattle chute. Once a cow is inside a cattle chute they are trapped and have no way out and have no choice but to go where the chute directs them.
A corridor traps people once they enter the corridor. The door self closes and may automatically lock behind (R-1) them leaving the occupant trapped in a narrow long tunnel with only two directions to travel. If the corridor becomes unusable due to smoke or fire it can quickly become death trap.

The Legacy Codes had a lot of fire requirements that are passive in the purpose and design. Allowing the removal of the required passive protection when built based on the newer codes because the building has a 40 year old sprinkler system installed is not something that I would want to explain to the court why I permitted the corridor to not maintain its original design (fire rated wall).
 
How do you Building Officials determine if an existing building equipped with automatic fire sprinklers is eligible to take the exception to 1 Hour fire rated corridors for a "B" occupancy from Table 1020.2?
Why wouldn't it? I think the "assumption" is that the building is fully sprinklered.....?
 
Why wouldn't it? I think the "assumption" is that the building is fully sprinklered.....?
Steve, The code exception allowing non rated corridors is based upon the fire sprinkler system being compliant at the time the exception came along.. Biggest issue would be that quick response heads would need to be present throughout. seismic restraints, flexible couplings and pipe clearances as well. Typically your looking at buildings that were constructed in 1996 and comply with 1996 edition of the NFPA 13, or newer.
 
Steve, The code exception allowing non rated corridors is based upon the fire sprinkler system being compliant at the time the exception came along.. Biggest issue would be that quick response heads would need to be present throughout. seismic restraints, flexible couplings and pipe clearances as well. Typically your looking at buildings that were constructed in 1996 and comply with 1996 edition of the NFPA 13, or newer.
What really needs to be done is a comparison of the old and new NFPA 13 docs.....I am betting the newer version is actually easier to comply with....I can argue it both ways, at least in my low seismic world....
 
What really needs to be done is a comparison of the old and new NFPA 13 docs.....I am betting the newer version is actually easier to comply with....I can argue it both ways, at least in my low seismic world....
What really needs to be done is that commercial real estate brokers that hear about a code change that would eliminate fire rated corridors if their building is sprinklered should not encourage building owners to add glass doors and sidelights throughout common corridors in old buildings without permits.
 
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