By RealCost Editorial TeamReviewed by RealCost Editorial TeamLast updated September 2, 2026 with 2026 data
Federal Pacific, Zinsco and Challenger panels have documented histories of breakers that fail to trip during an overload or short circuit, and most homeowners insurers will decline or refuse to renew coverage over the brand alone — no matter how much amperage the panel delivers or how it has performed for you. Insurance does not pay for the replacement it requires. Once you know the amperage the new panel needs to be, price the swap with the electrical panel upgrade cost calculator.
The replacement your insurer can force, independent of amperage
Every cost guide on the market prices a panel upgrade as a capacity decision: do you have enough amps for what you want to run. That framing misses a separate, purely insurance-driven trigger. Federal Pacific Electric (FPE) "Stab-Lok" panels were sold into millions of American homes between the 1950s and 1980s, and independent testing since has documented breakers that do not trip reliably during an overcurrent or short-circuit condition — the exact failure mode a breaker exists to prevent. Zinsco (sometimes labeled Sylvania) and Challenger panels carry similar documented histories.
Insurers have responded by treating the brand itself as the risk. A Florida insurance agency representing 26 carriers reports that 24 of those 26 will not write a new policy on a home with an FPE panel, and roughly 22 of 26 decline Zinsco/Sylvania or Challenger panels for the same reason. That is one agency's book of carriers in one state; no regulator or insurance-industry body publishes a national figure, so ask your own insurer how it treats these panels before you rely on any count.
Two things follow from that. First, a new policy application can be declined outright over the panel before anything else about the house is even considered. Second, an existing policy is not necessarily safe — if the panel turns up during a renewal inspection, an adjuster's claim visit, or a lender-required inspection at a refinance, a current insurer can non-renew or cancel at the next renewal date. Neither insurer pays to fix the problem they are requiring you to fix.
How to tell if you have one
Open the panel door and read the label on the interior of the cover or the breaker faceplates themselves:
- Federal Pacific Electric — labeled "Federal Pacific Electric" or "FPE," often with breakers branded "Stab-Lok."
- Zinsco — labeled "Zinsco" or, on some relabeled stock, "Sylvania."
- Challenger — labeled "Challenger."
If the label has worn off or the panel was relabeled at some point, a licensed electrician can usually identify the manufacturer on sight during any ordinary service call — worth asking about even if the visit was for something unrelated, since it is otherwise easy to live in a house for years without anyone checking.
How electricians actually size the replacement — not a rule of thumb
Once a panel is coming out, the next question is what amperage goes in. The common homeowner shortcut — "two or more big loads and 100 amp probably isn't enough" — is a reasonable gut check, but it is not what an electrician is required to use, and it is not how a quote that jumps straight to "you need 200 amp" should be justified. The actual method comes from NEC Article 220, and the version most electricians reach for on a service upgrade is the 220.82 optional method for single-family dwellings, because it is faster to run and usually returns a lower, still fully code-compliant number than the standard method:
- Multiply the home's habitable square footage (garages, porches and unfinished space excluded) by 3 VA per square foot for general lighting and receptacles.
- Add 4,500 VA fixed: 1,500 VA for each of the two required small-appliance circuits, plus 1,500 VA for the laundry circuit.
- Add the nameplate rating of the range, the dryer and the water heater.
- Add whichever is larger, heating or air conditioning — the two are treated as non-coincident loads and only the bigger one counts, not both.
- Apply the 220.82 demand factor: the first 10,000 VA of that total counts at 100%, and everything above 10,000 VA counts at 40%.
- Divide the resulting VA by 240 volts to get amps, then round up to the next standard service size — 100, 150 or 200 amp.
A quote that names an amperage without walking through something like this is not necessarily wrong — an electrician may be sizing for headroom you asked for, like a future EV charger or a heat pump conversion, which the calculation above does not know about unless you tell them to add it. But that reasoning should be stated to you, not left for you to assume. Once you and your electrician agree on the target amperage, price the job itself — panel, meter and mast scope, permit, and any rewiring — with the electrical panel upgrade cost calculator.
Before you get quotes
If you have an FPE, Zinsco or Challenger panel
- Call your current insurer before a renewal or claim surfaces it for you
- Ask any new insurer directly whether the brand is a condition of coverage
- Budget the replacement yourself — coverage does not fund it
When a quote names an amperage
- Ask whether it reflects your current load or planned future additions
- A load calculation is a normal, reasonable thing to ask an electrician to show
- 150 amp is a real middle option — don't let 100 vs. 200 be presented as the only choice
Run your numbers
Price the replacement, then check the insurance angle
Once you know the target amperage, price the panel, service entrance and permit — and check what a claim on the wiring itself would cost separately.
By RealCost Editorial TeamReviewed by RealCost Editorial TeamLast updated September 21, 2026 with September 2026 data
What the CPSC actually said in 1983
The most misused fact in Federal Pacific content is what the US Consumer Product Safety Commission concluded about the panels. It investigated FPE Stab-Lok two-pole residential breakers made before 1979, and in 1983 — a statement it revised in 2011 rather than retracted — it
That is a closed investigation, not a clearance. The Commission's own testing had confirmed these breakers "fail certain UL calibration test requirements" — real, documented test failures — but the agency said it did not have enough data either to accept or to refute the manufacturer's position that the failures don't create a household hazard, and its own note instructs electricians, inspectors and real estate agents to read the release carefully because it closed the matter "without making a determination as to the safety of FPE circuit breakers." There was never a CPSC recall of FPE panels, and the agency never declared them a fire hazard — both claims circulate widely and neither is accurate to the primary text.
The national fire data insurers are actually reacting to
Insurers don't need a brand-specific hazard finding to price risk conservatively on any older panel — the general trend in residential electrical fires is reason enough on its own. FEMA's US Fire Administration reports that in 2023, residential electrical-malfunction fires caused an estimated 23,700 fires, 305 deaths, 800 injuries and $1,501,600,000 in property loss nationally. Looking at the decade from 2014 to 2023, fires from this cause rose 2%, injuries rose 2%, dollar loss rose 28% after inflation, while deaths fell 19%.
None of this is a Federal Pacific, Zinsco, or Challenger statistic — it's an all-cause "electrical malfunction" category covering every panel brand, wiring age, and failure type nationwide. Cite it as background for why insurers underwrite electrical risk conservatively in general, not as evidence about any specific panel brand's failure rate.
Methodology
The CPSC history is quoted directly from the Commission's 1983 news release (revised 2011). Fire statistics are FEMA's US Fire Administration national estimates for 2023 and the 2014–2023 trend, an all-cause electrical-malfunction category not specific to any panel brand. Both figures are federal-agency primary sources; neither publishes a brand-specific carrier-refusal statistic, and none is cited here.