2009 ibc section if 506.4.1 Area determination ;allows 13R sprinkler area increase?

[syarn]

does 2009 ibc section 506.4.1 allow a 13R sprinkler system to increase the area of a building?

I was of the opinion that 13R only allowed height increase of 1 extra story and NO area increase.

506.4.1 Area determination. ....

Exceptions:

....

2. The maximum area of a building equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.2 shall be determined by multiplying the allowable area per story (Aa), as determined in Section 506.1, by the number of stories above grade plane.

 

[mtlogcabin]

506.4 is for single occupancy buildings only

The exception for area increase would only apply to R occupancies

 

[cda]

Exception 2 is an increase allowed for residential sprinkler systems installed in accordance with NFPA 13R. The area increases allowed by Section 506.3 are only applicable when the building is to be equipped with a sprinkler system in accordance with NFPA 13—not NFPA 13R. The three-story multiplier limit or "three-story cap" was initially evaluated based upon use of area increases resulting from the installation of an NFPA 13 system. Since buildings equipped with an NFPA 13R system are not allowed an area increase, it was determined that the "three-story cap" had an unintentional detrimental impact on residential buildings. Specifically, for a four-story residential building with an NFPA 13R sprinkler system, the provisions of Section 506.4.1 would reduce the area per story and the total building area. Given that the maximum height of buildings with NFPA 13R systems is four stories, this application of an increase in allowable area was determined to be warranted.

http://publicecodes.cyberregs.com/icod/ibc/2009f2cc/icod_ibc_2009f2cc_5_par025.htm

 

[Builder Bob]

Even with a 13R system, a developer designer can use the open area modifiers for increases..... and add an additional story.