Smoke and CO Alarms
Smoke alarms and carbon monoxide (CO) alarms are the warning devices California requires in homes. Every home needs smoke alarms, and a home with a fuel-burning heater or appliance, a fireplace or an attached garage also needs CO alarms. Both have to be models listed by the State Fire Marshal.
Where they go. Smoke alarms go in every bedroom, in the area just outside the bedrooms, and on every level of the house, including basements. CO alarms go outside the sleeping area and on every level, and inside a bedroom if a fuel-burning appliance is in that bedroom or its bathroom. Smoke alarms also have to stay at least 3 feet from the door of a bathroom with a tub or shower, and away from the stove.
Interconnected. In a new home, the alarms are linked so that one going off sounds them all. In an existing home the link is generally required when permitted work opens the walls or ceilings, or when an attic, crawlspace or basement gives a way to run the wire without opening them. Work only on the outside of the house, or on the plumbing, heating or electrical systems without opening finishes, does not trigger it. For CO alarms, listed wireless alarms that all sound together count.
Hardwired or battery. New homes need alarms powered by the house wiring with a battery backup. In an existing home where no construction is going on, battery-only smoke alarms are allowed, and so are battery or plug-in CO alarms in homes built before 2011. Since July 1, 2014, a battery-only smoke alarm sold in California has had to carry a sealed battery that lasts at least 10 years, so you replace the whole alarm rather than the battery.
Combination alarms that sense both smoke and CO are allowed in place of separate ones.
Also known as: Smoke detectorCarbon monoxide alarmCO detectorInterconnected smoke alarms10-year sealed smoke alarm
Why it matters in Santa Cruz County
The rules reach older homes in three ways. State law requires smoke alarms in every home, and CO alarms in homes with a fuel-burning heater or appliance, a fireplace or an attached garage, however old the house is. A single-family home that is sold has to have a working smoke alarm, and the seller signs a statement saying so. And when you pull a permit for alterations, repairs or additions, the home has to get smoke alarms everywhere current code puts them for a new house.
Sunrise's take
On an inspection we check for alarms in each required spot, whether a CO alarm is needed, and how old the alarms are. Where walls are already open or there is attic access, hardwired interconnected alarms are the setup we recommend, because one alarm then wakes the whole house.
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