Their code analysis is the most comprehensive I have seen, and the most wrong in many areas (mostly a lot of copy and past.....maybe AI generated?) Their little blurb on this makes me wonder if they think they get to ignore t506.2 because of 903.3.1.2. When I see a licensed professional architect that has such a difference in understanding from me I wonder if it is me or them. However, the more time I spend on this one it is becoming more clear.
1) No. If the Group A-2 occupancy is ancillary to the Group R occupancy, it can be sprinklered using NFPA 13R. For example, a Group R-1 hotel can have a restaurant within the building and be sprinklered using NFPA 13R, provided the building is within the height and area limitations for an NFPA 13R system. This has been supported by NFPA interpretation and commentary.
I have read several editions of NFPA 13R, and several opinions about this, but don't see any consistent or definitive answers for this issue. IBC 903.2.1.2 indicates if the A occupancy is not on the level of exit discharge, the 13R system can't be used. Can you point me to the interpretation and/or commentary? All I see in the annex is that if an accessory occupancy s properly separated from the residential occupancy, using 13R for the residential and 13 for the non-residential is appropriate. The condition I have is an accessory occupancy not separated from the residential occupancy. The accessory A is less than 10% of the floor in which it is located, so it could be an accessory mixed use and nonseparated, but if they separate it then the 13 would be required in that space only?
I asked this question of NFPA many years ago (nine to be exact) here is the response I received from a fire protection engineer at NFPA:
The above response is based on the 2013 edition of NFPA 13R. After reviewing the language of Section 1.1 in the 2013 and 2022 editions I have found that they are identical; however, the explanatory information in Annex A has changed over the years. Since the scoping language has not changed, I cannot see how the information in the Annex in the 2013 edition would not still apply.
does this conflict with the IBC and IFC? Table 504.3, 504.4 & 506.2 clearly identify allowable heights, number of stories and area for non sprinklered buildings, sprinklered single story buildings, sprinklered multi-story buildings and buildings with an residential 13R system. The 13R system isnt listed as an allowable option for any of the A occupancioes.
For occupancy groups without "S13R" values, they must use the "NS" values, since the "S1" and "SM" values require NFPA 13 per Section 903.3.1.1 as stated in the footnotes of each of those tables. Buildings will still be restricted in height and area as any other building, except that Group R buildings can be four stories (except for Type VB). However, if a Group A occupancy was within a predominantly Group R building and the occupancies were nonseparated, then the Group A occupancy would be the most restrictive, thus limiting the height to two or three stories (except for Type VB).
Section 903.3.1.2 states "Automatic sprinkler systems in Group R occupancies shall be permitted to be installed throughout in accordance with NFPA 13R..."