AFCI Requirements: The 2024 CEC Changes That Affect Every Residential Project

Arc faults cause an estimated 30% of electrical fires in Canadian homes. The CEC has been expanding AFCI requirements with every edition " and the 2024 code now covers nearly every branch circuit in a dwelling unit. Here's what changed and how to design for it.

What Is an Arc Fault?

An arc fault is an unintended electrical discharge " a spark jumping across a gap in damaged wiring, a loose connection, or a nail driven through a cable. Unlike overloads or short circuits (which trip standard breakers), arc faults generate low-level, intermittent energy that's hot enough to ignite wood and insulation but too small for conventional overcurrent protection to detect.

AFCI Types

Type	Detects	CEC Requirement
Combination AFCI (CAFCI)	Both series and parallel arc faults	Required for all new AFCI-protected circuits " this is the standard
Branch/Feeder AFCI	Parallel (line-to-line/line-to-ground) arcs only	Older type " no longer acceptable for new installations per 2024 CEC
AFCI Outlet (receptacle)	Downstream arc faults	Permitted as an alternative to breaker-type AFCI for renovations/extensions

CEC Rule 26-656: Where AFCI Is Required

The 2024 Canadian Electrical Code requires combination-type AFCI protection on the following circuits in dwelling units:

Circuit Type	AFCI Required?	Notes
Bedrooms	oe Yes	All 15A and 20A, 120V circuits " required since 2002
Living rooms, dining rooms, dens	oe Yes	Expanded in 2018 edition
Closets, hallways	oe Yes	Expanded in 2018 edition
Recreation rooms, sunrooms	oe Yes	2024 expansion
Kitchens	oe Yes	All 15A and 20A, 120V circuits " including lighting
Laundry rooms	oe Yes	120V circuits only
Bathrooms	s️ GFCI only	AFCI not required " GFCI protection governs per Rule 26-700
Garage	s️ GFCI only	GFCI protection per Rule 26-700
Outdoor	s️ GFCI only	GFCI protection per Rule 26-700
Dedicated appliance circuits (240V)	OE No	Range, dryer, A/C " not required
Fire alarm, security, sump pump	OE No	Life safety circuits exempt

2024 key change: The scope now covers essentially all 15A and 20A, 120V branch circuits in dwelling units except bathrooms, garages, outdoors (GFCI territory), dedicated 240V appliance circuits, and life safety circuits.

AFCI + GFCI: Dual Protection

Some locations require both AFCI and GFCI " such as kitchen countertop circuits (AFCI per 26-656, GFCI per 26-700). Solutions:

• Dual-function AFCI/GFCI breaker " single device, simplest solution
• AFCI breaker + GFCI receptacle " downstream GFCI at point of use
• AFCI breaker + GFCI deadfront " for hardwired applications

Nuisance Tripping - The #1 Complaint

AFCI breakers are sensitive by design, but nuisance trips frustrate homeowners and contractors. Common causes and solutions:

Cause	Solution
Shared neutral between circuits	Ensure each AFCI circuit has its own dedicated neutral " no shared neutrals
Long home runs (>30m)	Reduce circuit length or increase conductor size to reduce capacitive leakage
Incompatible LED dimmers	Use AFCI-compatible dimmers (check manufacturer's compatibility list)
Treadmills, vacuums with brushed motors	These generate normal arcing " modern CAFCI breakers are designed to distinguish; upgrade older AFCI if tripping persists
Loose wire connections	Torque all connections to manufacturer specs " loose wires create real arc faults

Installation Requirements

• AFCI breakers require a dedicated neutral pigtail connected to the panel neutral bar
• Panel must have sufficient space " AFCI breakers are full-size only (no tandem/slim)
• Monthly test button verification required by manufacturer
• AFCI outlet devices (receptacle type) are acceptable for renovations and circuit extensions where replacing the breaker is impractical

Frequently Asked Questions