(1) Where the performance level of an existing building is reduced under Sentence 11.4.2.2. (1), (2) or (3), the building shall be evaluated, and the early warning and evacuation systems shall be upgraded, in conformance with the applicable requirements of Table 11.4.3.3.
(2) Sentence (1) does not apply in a Group C occupancy where the new total occupant load is,
(a) 14 persons or fewer in a boarding, lodging or rooming house, except that where the occupant load is between 10 and 15 persons, an interconnected system of smoke alarms in corridors near stairways is required, or
(b) 16 persons or fewer in a building containing residential suites which are dwelling units, except that where the occupant load is between 10 and 17 persons, an interconnected system of smoke alarms in corridors near stairways is required.
(3) Where the performance level of an existing building is reduced under Sentence 11.4.2.2. (1), additional construction shall be required in order that the building or part of the building subject to the increase in occupant load conforms to the requirements of Sentence 6.2.2.1. (2), Subsection 3.7.4. and Article 9.31.1.1.