Hard-wired, interconnected smoke alarms: what changes when you renovate

Where they’re needed

In a dwelling, the building rules require smoke alarms on every floor, including the basement, and near the bedrooms; depending on the layout, in each bedroom. The exact requirements depend on the regulations in force and the type of work: we apply them in the quote.

Who sets these rules? For a house, Québec.ca suggests checking with the municipality for the regulations in force and the type of alarm allowed. Québec’s Electrical Code, 2026 edition, refers to the National Building Code for installing smoke and carbon monoxide alarms in dwellings. And for apartment buildings and condominiums, the RBQ requires an alarm in the rooms where people sleep or in the hallway serving them, and one on each floor of a two-storey unit.

What Québec.ca recommends, for every home:

Placing it right

According to Québec.ca:

• on the ceiling, at least 10 cm from the wall, or on the wall, 10 to 30 cm from the ceiling;
• 1 m from a fan, an air conditioner, an outlet or a return-air vent;
• unobstructed, so the smoke can reach it.

Everyone in the home must hear it when it goes off. Also avoid the kitchen and the bathroom: it goes off there for nothing.

Interconnected: when one sounds, they all sound

A fire that starts in the basement at night has to wake someone upstairs. Hard-wired, interconnected alarms do that: they are linked together, with a backup battery in case of an outage. That’s what new work requires and, often, renovations that open walls or create a bedroom.

If your hard-wired alarms don’t sound together, Québec.ca recommends having them interconnected by a qualified electrician.

Hard-wired or battery

Battery alarms have their place as a complement, but they don’t sound together and they depend on a battery people forget. Hard-wired models with battery backup are the norm in construction and renovation.

Carbon monoxide

If the house has a fuel-burning appliance (furnace, fireplace, gas water heater) or an attached garage, a carbon monoxide alarm is also required near the bedrooms. Combined smoke and CO models exist.

• For apartment buildings, the RBQ requires one if there’s a fuel-burning appliance or direct access to an indoor garage, with a device that meets standard CAN/CSA-6.19 and has a built-in alarm.
• An ordinary smoke alarm doesn’t detect carbon monoxide: according to the City of Sherbrooke, only combined models detect both.
• The City recommends a carbon monoxide alarm with a battery that keeps it running during an outage and the CSA 6.19 certification logo.

A generator running too close to the house is a source of carbon monoxide; see Generators and transfer switches.

Ten years, no more

A smoke alarm is replaced after ten years: the manufacturing date is printed on it. An alarm that goes off for no reason is often at the end of its life, or poorly placed near the kitchen or bathroom.

The RBQ adds: with no manufacturing date, or if it’s unreadable, the alarm is replaced right away. The City of Sherbrooke also reminds us: battery or hard-wired, they’re changed every 10 years.

Checking them

• Every month: press the test button for a few seconds (Québec.ca).
• When the clocks change, in spring and fall: a good time to check the batteries (City of Sherbrooke).
• Never paint them.
• A system connected to a monitoring centre doesn’t replace an alarm required by the municipality; notify the centre before a test.

When renovating

When you add a bedroom in the basement or open walls, that’s the time: the wiring is done with the rest, without much extra work. We tell you in the quote what the rules require for your project. See also Finishing a basement: the electrical work.

With LTE Électrique

We install and interconnect hard-wired alarms, smoke or combined smoke and carbon monoxide, during your work: renovation, basement, new bedroom. The price is announced in advance, fixed or hourly depending on the project, and labour is guaranteed for 2 years. Send us the number of floors and bedrooms, and a photo of an alarm: the estimate is free, within 24 hours.