Architect reviewing an existing building for code compliance. The Authority Having Jurisdiction (AHJ) has informed us that the entire building must meet all the requirements of Chapter 38 for New Business and all related chapters (7, 8, etc.). They have specifically told us that this building must be treated as a "new" building (event though it is existing and we are not changing occupancy classification) in order for them to consider the Owner's application for this project. My question is regarding table 18.104.22.168. The existing stairwells are 1-HR fire barriers with 45 min rated doors. The way I am reading the table, stairwells fall under vertical shafts, so stairwells that are 1-HR should have 60 min doors so I believe the existing doors would need to be replaced. Does this seem like a correct interpretation?