sprinklernotes
Balconies as Part of the Dwelling Unit
“Are balconies accessed from dwelling units considered part of the dwelling
unit? Would sprinklers on dry pipe systems protecting these balconies be
required to meet the 15-second water delivery time requirement?”
We have reviewed NFPA 13, Standard for the Installation of Sprinkler Systems,
2016 edition as the applicable standard. Our informal interpretation is that
the balconies attached to dwelling units are not a part of the dwelling unit
and do not have to meet the 15-second water delivery time requirement.
Although a balcony is adjacent to a dwelling unit, it is not considered a part
of the dwelling unit similar to a corridor. The definition for dwelling unit
states, “one or more rooms arranged for the use of one or more individuals
living together, as in a single housekeeping unit normally having cooking,
living, sanitary, and sleeping facilities that include, but are not limited to,
hotel rooms, dormitory rooms, apartments, condominiums, sleeping rooms in
nursing homes, and similar living units.” This definition focuses on “rooms”
for living. Exterior projections are not included as part of the dwelling unit
since they are addressed in section 8.15.7. Location has meaning. With that
said, a balcony can be protected by a residential sprinkler. Section 8.4.5.1
says that residential sprinklers shall be permitted in dwelling units and their
adjoining corridors, provided they are installed in conformance with their
listing. The annex section A.8.4.5.1 indicates that the response and water
distribution pattern of listed residential sprinklers have been shown by
extensive fire testing to provide better control than spray sprinklers in
residential occupancies. These sprinklers are intended to prevent flashover in
the room of fire origin, thus improving the chance for occupants to escape or
be evacuated. Section 7.2.3.1.1 states, “For dry pipe systems protecting
dwelling unit portions of any occupancy, system size shall be such that initial
water is discharged from the system test connection in not more than 15
seconds, starting at the normal air pressure on the system and at the time of
fully opened inspection test connection.” While this references “dwelling unit
portions of any occupancy,” it could be argued that a balcony is not a part of
a dwelling unit. Since the balcony in open to the atmosphere, the likelihood
of the balcony reaching the condition of flashover or someone becoming trapped
by fire is very remote. As such, the water delivery within 15 seconds is not
imperative since sprinkler protection of balconies is provided primarily for
property preservation.
