Why do smoke alarms go off in cold weather?

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Smoke alarms are essential. A home that is not outfitted with an alarm or, preferably, with more than one, is putting its occupants at risk. When smoke alarms are installed in a home or any type of building the chance of an occupant dying in a fire is cut in half, according to Usfa.dhs.gov.

However, sometimes smoke alarms can act up and start beeping for what appears to be no apparent reason. This often occurs during cold weather.


According to Firexsafety.com, an alarm can be activated due to water vapour, which is condensation that occurs in the detection chamber of the smoke alarm. The sensor in the alarm senses particles. When water condenses in the chamber, the alarm will start beeping. This is apt to occur when it is extremely cold outside.


It is a good idea to put a smoke alarm in a garage or attic; however, it can get really cold in these areas so choose an alarm that is not impacted by condensation.


Perhaps your smoke alarm is located too close to the bathroom and is being affected by the steam escaping from within. This may cause it to beep because condensation can get inside of the alarm chamber. If the alarm is situated too closely to a door that opens to the outside, it may beep.

Turn Up Your Thermostat

If the alarm intuits that the temperature in your house is too cold, it may begin beeping or chirping. Turn your thermostat up a bit and see if this quells the beeping.


Alarms can be tricked into going off by steam or smoke from cooking. If this happens repeatedly, consider moving the alarm to a new position that is farther away from the cooking area so that it won’t respond to steam or the vapours from cooking.


When purchasing a smoke alarm, buy one that either has a photoelectric sensor or an ionisation sensor. A photoelectric sensor uses a light source that shines on a light sensitive sensor in the alarm. When smoke from a fire interferes with the light, the alarm goes off. An ionisation alarm uses a small quantity of radioactive material that prompts the air in the alarm chamber to conduct electricity. Smoke from a fire will interfere with the electrical current, and that is what sets off the alarm. The smoke alarm that you purchase should be approved by a testing laboratory.