What is a mains powered smoke alarm?

Mains-powered smoke alarms draw their operating power directly from the building's electrical grid.

They typically include a battery (either a replaceable or sealed 10-year lithium-ion battery) to provide power in the event of a power outage.

Mains-powered alarms are generally considered more reliable than battery-powered alarms because they don't rely solely on batteries that can be forgotten, drained, or disconnected.

Many mains-powered smoke alarms can be interconnected, meaning that if one alarm detects smoke, all interconnected alarms in the system will sound. This is particularly useful in larger homes or buildings.

Mains-powered smoke alarms usually need to be professionally installed by a licensed electrician due to the electrical connection.

In many areas, new construction, renovations and extensions (such as loft conversions or new habitable rooms) require mains powered alarms with interconnection.

The main advantages include constant power, reduced maintenance (no need to constantly change batteries) and the ability to interconnect for wider coverage.