DEVELOPMENT SERVICES
Building and Safety
(949) 461-3470
SMOKE DETECTOR & CARBON MONOXIDE ALARM
RETROFIT/VERIFICATION REQUIREMENTS
Please be advised that the 2019 California Building Code (CBC) and the 2019 California Residential Code
(CRC), effective on January 1, 2020, require smoke detectors and carbon monoxide alarms to be installed
in prescribed locations as part of a permitted residential construction project value at $1,000 or more. See
NOTES below.
Smoke detectors are required to be mounted on the ceiling or wall and located as specified below. If
retrofitted, detectors may be battery operated (Code references: CBC § 907.2.10.2 and CRC § R314)
• Outside of each separate sleeping area in the immediate vicinity of bedrooms
• In each room used for sleeping purposes
• In each story within a dwelling unit, including basements, but not including crawl spaces and
uninhabitable attics. In dwellings or dwelling units with split levels and without an intervening
door between the adjacent levels, a smoke alarm installed on the upper level shall suffice for the
adjacent lower level provided that the lower level is less than on full story below the upper level.
Carbon monoxide alarms are required to be mounted on the wall or ceiling or other location as specified
in the manufacturer’s installation instruction and located as specified below. If retrofitted, alarms may be
battery operated where the repairs or alterations do not result in removing wall and ceiling finishes or
there is no access to the attic, basement, or crawl space (Code references: CBC § 915 and CRC § R315).
• Outside of each separate sleeping area in the immediate vicinity of bedrooms
• On every level of the dwelling unit
• For R-1 Occupancies only – on the ceiling of sleeping units with permanently installed fuel
burning appliances
Inspection verification on existing or retrofitted smoke detectors and carbon monoxide alarms will be
verified during the inspection process as follows:
Reroof – at time for sheathing
Attached Patio Covers – at footing inspection
Swimming Pools & Spas – at fence and gate inspection
Solar Panels – at final
NOTES:
1. These requirements only apply to the dwelling unit(s) for which the permit applies. For example,
if an apartment building roof is replaced all the units within the building would be required to be
retrofitted/verified to have the detectors and alarms. For an interior remodel of a single unit, only
that unit would be required to be retrofitted/verified.
2. Carbon monoxide alarms are not required for dwellings that do not have fuel burning appliances,
fireplaces, or attached garages.
3. Self-verification may be substituted for inspection using the: Smoke Detector and Carbon
Monoxide Self-Certification form (see other side).
ADVISORY: Smoke detector and carbon monox
ide alarm retrofit/verification requirements
for residential construction projects effective January 1, 2020.