My question is : How does one measure square footage for particular areas of Code that trigger specific items?
Example: I have a new school (education) that is 11800sf with a 500sf non occupied HVAC 2nd floor. NFPA 101 18.104.22.168 (2015 edition) requires sprinklers in educational occupancies over 12000sf. Do I count only occupiable space (11800sf)? Do I count all square footage under roof (including attached covered porches/overhangs)? or do I count HVAC area with both floors (total of 12300sf)? Is there any where in Code that this is clarified (how to measure for this)? Am I over looking something so simple?
My problem: I have an architect saying that only occupiable stories are counted. He is referencing commentary in the annex for the definition of occupiable story (101:3.3.268.1). While I responded with this is only a definition, I have nothing to hang my hat on as to how square footage is determined for 101:22.214.171.124 (or any other Code requirement based on square footage).