Residential electrical panel breaker box with open door showing rows of circuit breakers
    Specialist confirmation

    Zinsco (Sylvania) Electrical Panels

    Fire hazards from breakers that fuse to the bus bar — common in Canadian homes built 1950–1980

    Quick Overview

    Zinsco panels — also sold as Sylvania and GTE-Sylvania — were widely installed in Canadian homes from the 1950s through the 1970s. The breakers are prone to fusing or welding to the aluminum bus bar, which means they cannot be reset and fail to trip under overload, creating a serious fire hazard.

    Common in homes:1950–1980
    Safety risk:High
    Insurance issues:Possible — confirm with insurer
    Solution:Licensed electrician assessment

    How to Identify

    • • "Zinsco", "Sylvania", or "GTE-Sylvania" name on the panel
    • • Colourful breaker handles — red, blue, or green
    • • Thin, narrow breaker slots packed closely together
    • • Home built between 1950 and 1980
    • • Aluminum bus bar visible inside the panel cabinet
    • • May show signs of scorching or discolouration around breakers

    Major Risks

    • • Breakers fuse to the aluminum bus bar and cannot be reset
    • • Arcing and overheating inside the panel cabinet
    • • Breakers fail to trip under overload — primary fire hazard
    • • No longer CSA-approved for new installations
    • • Possible insurance complications — confirm with your insurer
    • • May be a concern during home inspections

    Understanding Costs

    Costs for panel replacement, inspection, permits, and any related service upgrade vary by province, service size and contractor.

    Ask for itemized written quotes from licensed master electricians and confirm the required electrical permit is included.

    Professional Recommendations

    Immediate Actions:

    • • Have panel inspected by a licensed master electrician
    • • Contact your insurer — disclose the panel type now
    • • Do not attempt to modify or swap breakers yourself
    • • Check for any signs of scorching inside the panel cabinet

    Long-term Solutions:

    • • Replace the entire panel with a CSA-approved load centre
    • • Consider upgrading to 200A service at the same time
    • • Pull the required ESA or AHJ permit — do not skip this step
    • • Get a letter of compliance from your electrician for your insurer

    Common questions

    Frequently Asked Questions About Old Canadian Houses

    Common questions from buyers and owners of older Canadian homes, answered with era context and pointers to the professionals who can confirm anything on a specific property.

    Have a question not answered here? Browse our full inspection guide or explore all resources.