How to Install a Motion Sensor Light Switch?

A motion sensor light switch is one of the cheapest upgrades that pays back the fastest — a $30 device that saves a few dollars a month on lighting and stops the whole family from leaving a basement or laundry room light on for hours. This guide walks GTA homeowners through how to install a motion sensor light switch safely, which sensor type matches which room, and where the Ontario Electrical Safety Code draws the line between a simple homeowner swap and licensed-electrician work.

Quick answer: how to install a motion sensor light switch

Direct answer: kill the breaker, remove the existing single-pole switch, connect the sensor’s line lead to the incoming hot conductor, the load lead to the outgoing hot conductor, the ground lead to the bare copper bond, and — if the sensor requires it — the neutral lead to the white conductor in the box. Fold conductors carefully into the box, screw the sensor in place, restore power, and set the dwell time and sensitivity dials.

Pick the right sensor for the room

Direct answer: match the sensor technology to how the room is used. Passive infrared (PIR) sensors detect body heat and work well in laundry rooms, closets, and hallways. Ultrasonic sensors detect motion by sound reflections and work in bathrooms where PIR is blocked by shower curtains. Dual-technology sensors combine both and are best for offices and multi-use rooms.

• Closets, pantries, small hallways: PIR occupancy sensor, 5-10 minute dwell
• Bathrooms: ultrasonic or dual-tech vacancy sensor, 15-20 minute dwell
• Laundry rooms, mudrooms: PIR occupancy sensor, 15-20 minute dwell
• Home offices, family rooms: dual-tech vacancy sensor with manual on and automatic off
• Basement stairs and utility rooms: PIR with a wide field of view and a longer dwell so the light does not drop mid-task

Amir Azimipour

Electrician Since 2008 Journeyman Electrician Designated Master Electrician at EZSMART Corp