In NBC, it's required. with exceptions.
3.2.4.8.
Annunciator and Zone Indication
1) Except as permitted by Sentences (3) to (5), an annunciator shall be installed in close proximity to a building entrance that faces a street or an access route for fire department vehicles that complies with Sentence 3.2.5.5.(1).
2) Except as permitted by Sentence (6), the annunciator required by Sentence (1) shall have separate zone indication of the actuation of the alarm initiating devices in each
a) floor area so that the area of coverage for each zone in a building that is not
sprinklered is not more than 2 000 m2,
b) floor area so that the area of coverage for each zone is neither
i) more than one storey, nor
ii) more than the system area limits specified in NFPA 13, “Installation of Sprinkler Systems,”
c) shaft required to be equipped with smoke detectors,
d) air-handling system required to be equipped with smoke detectors,
e) fire extinguishing system required by NFPA 96, “Ventilation Control and Fire Protection of Commercial Cooking Operations,”
f) contained use area,
g) impeded egress zone, and
h) fire compartment required by Sentence 3.3.3.5.(2).
(See Note A-3.2.4.8.(2).)
3) An annunciator need not be provided for a fire alarm system if not more than one zone indicator is required by Sentence (2).
4) If an annunciator is not installed as part of a fire alarm system in conformance with Sentence (1), a visual and audible trouble signal device shall be provided inside the main entrance of the building.
5) The requirements of Sentence (1) are waived in a building
a) in which an automatic sprinkler system is not installed,
b) that has an aggregate area for all storeys of not more than 2 000 m2, and
c) that is not more than 3 storeys in building height.
6) The area limits of Clause (2)(a) are waived for an interior undivided open space used as an arena, a rink, or a swimming pool provided that other spaces in the building that are separated from the open space are individually zoned in accordance with the requirements of Sentence (2).
7) A fire alarm control unit installed in close proximity to a building entrance that faces a street or an access route for fire department vehicles that complies with Sentence 3.2.5.5.(1) is deemed to satisfy the requirement for an annunciator, provided all indicators required for an annunciator or trouble signal device are included on the control unit.
