Smoke Detector Locations
Not long ago I inspected a 70’s era townhouse near downtown Palo Alto. The home had been recently re-painted and the agent wanted to know where the smoke detectors should be placed. Since the home was three floors and had four bedrooms, seven smoke detectors were required. Current NFPA standards require a smoke detector in each bedroom and a detector on each level of the home.
So… for a typical single story three bedroom and two bath home, 4 smoke detectors are usually needed: one in each bedroom and one the bedroom hallway. This all makes sense, since the entire purpose of smoke detectors is to wake anyone who is sleeping when a fire breaks out. In a two story home, with the bedrooms upstairs and the living areas downstairs, you’ll need an extra smoke detector on the lower floor ideally near the stairway leading up to the bedrooms. On larger homes with long hallways, you may need more than one detector in the bedroom hallway since they need to be within 10 feet of the bedrooms.
Smoke detectors generally fall under two classifications: ionization and photoelectric. Despite the widespread availability and use of ionization detectors, extensive research indicates that ionization type detectors respond quickly to flames but respond slowly to smoke during a fire. Ionization detectors have poor rating in detecting smoldering fires. Just check out YouTube for some pretty convincing evidence. Most fatal fires occur during sleeping hours, and most deaths are caused by smoke inhalation rather than flames. Wells Home Inspection recommends the exclusive use of photoelectric type smoke detectors.
Carbon Monoxide detectors are the topic of my next blog, and for most homes are
required along with the smoke detectors. More on that next week!