The city of Vancouver electrical code requires that every home has 120 volt smoke detectors installed before an Occupancy Permit will be issued. As a result, electricians will always install these ‘regular’ detectors in order to meet the code. Often, homeowners assume that those smoke detectors are being monitored by their alarm system… they rarely are.
Unfortunately, the city code does not yet recognize the superiority of having monitored, low voltage smoke detectors installed in your home.
What’s the difference between a ‘regular’ smoke detector and a monitored, low-voltage version?
Some of the advantages of a monitored, low-voltage smoke detector include:
- They are monitored through the alarm system… in the event of a fire (or the presence of smoke), we’ll know about it within seconds (even faster if you have BLINK);
- Because they are monitored through the alarm, a signal is sent to us to indicate that a detector has lost power or is using a back-up battery;
- the ability to pinpoint exactly which detector is in alarm;
By contrast, when the regular 120 volt detectors trip, they just make a noise… and if the power goes out, they will only last as long as the battery that you’ve installed in it (assuming it works).
This is why you often see homes with two smoke detectors side-by-side (like the photo below)… one is to meet the city electrical code… and one that is connected to the alarm system (either hardwired or wireless).
120Volt Smoke Detectors can be monitored… but are not the best way to go
While devices exist that allow us to connect your alarm to the 120 volt smoke detectors, we find that this practice invariably causes confusion later on… not the least of which is the fact that when any smoke detector in the house trips, all we know is that a fire alarm has tripped, not the exact location, or which specific detector, tripped. This is because 120 Volt detectors are ‘daisy-chained’ when wired… meaning that each detector is connected to a single cable. With low voltage detectors, each device is wired directly to the panel (or sends a wireless signal to the panel) without any ‘sharing’.
Daisy chain wiring creates a lot of frustration and wasted time for clients, the Fire Department and our Technicians when we are trying to troubleshoot why an alarm occurred … because all we know is that there was an alarm, but not the specific location from where it originated.
By contrast, with monitored low voltage detectors, we know immediately that an alarm is coming from the master bedroom smoke detector, or the basement electrical room or the garage, or wherever… giving the Fire Department much better information while they are en-route to your home.
False Alarm Issues
Because one of the most common reasons for smoke detectors tripping is burning something in the kitchen, clients invariably end up disconnecting the 120 volt smoke detector closest to the kitchen.
For this reason, we recommend that those ‘regular’ smoke detectors NOT be connected to the alarm. Instead, we install low voltage smoke detectors, designed to be remotely monitored, outside of each bedroom and in the basement… never anywhere near the kitchen.
Another advantage of low-voltage smoke detectors over the 120 volt ones is aesthetics. In many new residential projects, we are installing a flush-mount detector. The photo below shows one installed in our Kerrisdale showroom. 
While it is several times as expensive as a regular detector, it is the only flush mounted design that I have seen that really works.
The photo isn’t great, but it shows the smoke detector in the top right corner along with a small pot light and a ceiling mounted motion detector. Please feel free to stop by our showroom at 2309 West 41st Avenue if you would like to see how it looks installed.
What should you do?
1. Determine if your existing smoke detectors are monitored or not (call your alarm company and ask);
2. If your smoke detectors are more than 3 years old, consider having them replaced… if they are more than 5 years old, definitely have them replaced;
3. If you only have 120 Volt smoke detectors installed, consider having monitored low voltage smoke detectors added to your system (they can be either hardwired or wireless).