Mixing NFPA 13 and NFPA 13R

[RLGA]

Looking for an answer from fire protection engineers and fire plans examiners.

A building with Type IA construction on first floor (commercial retail) with Type IIIA construction for 4 stories above (residential apartments) and a 3-hour horizontal assembly between the two construction types per Section 509.2 (2009 IBC).

Since an NFPA 13R cannot be used for the first story, can the building (technically, they are two buildings) have a mix of NFPA 13 for the first story and NFPA 13R for the residential stories?

 

[jar546]

That is a really interesting question since NFPA talks about number of stories. Just because there is a separation does not mean it is a 4 story building. It is still a 5 story building whether or not it is separated. I am taking the position that the building must be NFPA13.

 

[RLGA]

Here's my interpretation that would seem to allow it:

IBC Section 903.3.1.2 states "Group R occupancies up to and including 4 stories in height..." Notice it doesn't state "buildings," but states "Group R occupancies." In my example building, the Group R occupancies do not exceed 4 stories in height.

NFPA 13R Section 1.1 states "residential occupancies up to and including four stories in height in buildings not exceeding 60 ft (18 m) in height above grade plane." Again, it states up to four stories of residential occupancy, and only refers to the grade plane when specifying the maximum height in feet. Thus, if my example building does not exceed 60 feet in height (it is limited to 65 feet per Table 503), then it seems to also comply with NFPA 13R.

The explanatory information for Section 1.1 of NFPA 13R states "Where buildings of mixed use can be totally separated so that the residential portion is considered a separate building under the local code, NFPR 13R can be used in the residential portion while NFPA 13 is used in the rest of the building." I can see where this would be applicable if a fire wall was used, but Section IBC 509.2 is rather unique. IBC Section 509.2 states that the "building shall be considered as separate and distinct buildings for the purpose of determining area limitations, continuity of fire walls, limitation of number of stories and type of construction..."--thus, the horizontal assembly creates separate buildings for those purposes and does not mention fire protection. On the other hand, IBC Section 706.1 for fire walls states only that a building divided by fire walls "shall be considered a separate building." Period.

Maybe I should get an ICC staff opinion.

Does anybody else have an opinion?

 

[cda]

Yes I would say you can, sorry no back up

 

[cda]

4. The Title of NFPA 13R

While the early editions of NFPA 13R left the decision to the applicable building code to determine how the four-story limit was to be measured, a question remained as to what the committee had intended. Some would argue the intent of NFPA 13R has been to allow a four-story residential occupancy constructed above a non-combustible podium to use an NFPA 13R sprinkler system in lieu of the NFPA 13 sprinkler system. The idea of allowing a podium approach has often been rejected simply based on the title of the document, which as originally developed and interpreted has been assumed to set a limit of four stories to the entire building. This approach prohibited the use of a 13R sprinkler system in a four-story portion of a building that is constructed above a non-combustible podium.

To clarify this application, the Technical Committee for Residential Sprinkler Systems approved a recommendation to revise the title of NFPA 13R to “Standard for the Installation of Sprinkler Systems in Low-Rise Residential Occupancies.” This change provides a general description of the requirements outlined in the standard, while leaving the actual scope of the document to Section 1.1.

NFPA :: News & Publications :: NFPA Journal® :: Archived Issues :: May/June 2012 :: Features

 

[cda]

Direct from the nfpa mouth

Now will the ahj go for it???

 

[RLGA]

Awesome, cda! That answers my question very succinctly.

 

[jar546]

Wow, there you have it right from the horses mouth. I stand corrected. I don't agree but I stand corrected.

Once again I have learned something and at some humble pie.

 

[cda]

Wow, there you have it right from the horses mouth. I stand corrected. I don't agree but I stand corrected.Once again I have learned something and at some humble pie.

Not the first time ibc and nfpa did not match

Plus both have the same terms that do not agree

 

[FM William Burns]

Does anybody else have an opinion?

13 R Handbook Does:

Where buildings of mixed use can be totally separated so that the residential portion is considered a separate building under the local code, NFPA 13R can be used in the residential portion while NFPA 13 is used in the rest of the building. Examples of accessory occupancies found in NFPA 13R installations can include parking garages/areas, community laundry rooms, clubhouses, exercise facilities, tenant storage, and so forth.