The parts of the system
Service entrance. Overhead or underground conductors from the utility to the meter. Inspectors look at the drop clearance, mast and weatherhead, and the condition of the meter base.
Main panel. The service size (often 100, 125 or 200 amps), the main disconnect, breaker types and sizes, wire gauge, grounding and bonding, and signs of overheating such as melted insulation or scorched bus bars.
Subpanels. Separation of neutral and ground conductors, which is required in subpanels and often done wrong.
Branch circuits. Visible wiring in the attic, garage and crawlspace, junction boxes with covers, and splices made inside boxes rather than in open air.
Devices. Outlets, switches and fixtures for function, polarity, grounding and protection.
Panels with a reputation
Some brands appear again and again in inspection reports:
- Federal Pacific Electric (Stab-Lok): breakers were found to fail to trip under overload in independent testing. Most inspectors recommend evaluation and replacement.
- Zinsco and Sylvania-Zinsco: breakers can fuse to the bus bar, and the aluminum bus is prone to overheating.
- Fused panels: not inherently unsafe, but often undersized for a modern house, and easy to over-fuse.
Protection devices
GFCI (ground-fault circuit interrupter) protection prevents shock in wet locations. Modern code expects it in bathrooms, kitchen counters, garages, exterior outlets, crawlspaces, laundry areas and near sinks. Older homes were built before these rules, so inspectors report missing GFCI as a safety upgrade rather than a code violation.
AFCI (arc-fault circuit interrupter) breakers reduce fire risk from damaged wiring. They are required in more rooms with each code cycle and are common in newer construction and remodels.
Common findings
- Double-tapped breakers, where two wires share a terminal not rated for two.
- Open grounds or reversed polarity at outlets.
- Missing knockouts or blanks in the panel cover.
- Extension cords used as permanent wiring.
- Ungrounded three-prong outlets installed to replace two-prong ones.
- Exposed splices or Romex in reach in a garage.
- Aluminum branch wiring from the 1960s and early 1970s.
Solar, batteries and EV chargers
Inspectors note the presence of solar inverters, battery storage and EV chargers, and will report visible defects. Detailed evaluation of these systems is outside most standards of practice. Ask the seller for permits, the interconnection agreement and any lease or loan paperwork.
When to call an electrician
Any finding involving the main panel, overheating, aluminum wiring or unpermitted work should go to a licensed electrician (C-10 license in California) for an estimate during your contingency period.
Common questions
Is a Federal Pacific panel a deal breaker?
Not usually. It is a known issue with a known fix. Many buyers negotiate a credit for a licensed electrician to replace the panel, which often costs a few thousand dollars depending on the service size and the work needed.
Does the inspector test every outlet?
Inspectors test a representative number of accessible outlets, plus all GFCI devices they can reach. Outlets behind furniture or stored items may be skipped and are noted as inaccessible.
My house has two-prong outlets. Is that a problem?
Two-prong outlets usually mean ungrounded wiring, common in houses built before the 1960s. It isn't automatically unsafe, but grounded appliances and surge protectors don't work as intended. Options include rewiring, adding grounds, or installing GFCI protection on those circuits.