What Are the Odds of Having an Electrical Fire?
Low in any single year, but wiring over 30 years old raises the risk enough that insurers often flag it before renewal.
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When old wiring is the reason behind the letter
If the notice named wiring or electrical risk, the insurer is probably pointing to the age of the house, not an actual fire or claim on your record. Knob-and-tube and early aluminum wiring are the two types insurers flag most, since both carry higher failure rates than modern copper. An inspection report, if one was mentioned in the letter, is doing the same job an underwriter would do in person. If a licensed electrician inspects the panel and wiring and brings anything outdated up to code, that report can sometimes reverse a non-renewal or at least help when shopping for a new policy, since the risk the insurer flagged no longer applies. Your declarations page or the letter itself should say exactly what was found.
A non-renewal over wiring doesn't mean your house is unsafe to insure, it means one insurer priced the risk and walked away. Other insurers weigh old wiring differently, and some won't blink at a house your current one dropped. Rebuilding cost, lender deadlines, and what the letter actually flagged all factor into what you'd pay elsewhere. Comparing quotes now shows whether that number is fair before the deadline forces a rushed decision.
Why insurers treat wiring differently than most other risks
Most causes of loss get priced the same everywhere. Wiring is different because it's one of the few risks an insurer can actually see and measure before a fire ever happens. A roof's age shows up in a photo. Wiring type shows up in a panel inspection or a permit record tied to the house's build year. That's why insurers lean on inspection reports for electrical risk more than for almost anything else they underwrite.
The odds themselves are not the main issue. Electrical fires are a small share of home fires in any given year, and most houses with older wiring never have one. What drives the decision is cost if it happens. Knob-and-tube wiring lacks a ground wire and was never built for the electrical load a modern house draws. That raises both the chance of an arc fault and the cost to rebuild if one starts behind a wall. Aluminum wiring from the 1960s and 70s has a known weakness at outlets and switches, where connections loosen over time and heat builds up. Insurers aren't guessing at these patterns. They're pricing a failure mode that's well documented in older housing stock.
Rewiring matters more to an insurer than almost any other home improvement for this reason. A new roof extends a timeline. Updated wiring removes the specific hazard the policy was flagging. Some insurers will ask for proof the work was done by a licensed electrician and permitted through the local building department, not just completed. Keep that paperwork, since it answers the exact question the next insurer's underwriter will ask.
A house with original wiring isn't uninsurable. The pool of insurers willing to take it on is smaller, and the ones that do often price it as a known, bounded risk rather than a surprise. Some ask for a four-point inspection, covering wiring, plumbing, roof, and HVAC, before issuing a policy on an older home at all. Having that done ahead of applying, rather than waiting for an insurer to request it, can shorten the time between a non-renewal and a new policy taking effect.
What actually causes an electrical fire in a house
Most electrical fires start at a connection, not inside a wire itself. Loose connections at outlets, switches, or the breaker panel create resistance. Resistance creates heat. Over years, that heat degrades the insulation around it until something arcs. This is why age and wear matter more than how the house is used day to day.
Overloaded circuits are the other common cause. A circuit built decades ago for a few lamps and a radio now carries space heaters, window units, and a kitchen full of appliances. The wire itself may still be sound, but the breaker protecting it, or the lack of one sized for modern loads, is doing more work than it was designed for. This is a different problem from old wiring, and it can show up in a newer house too if circuits were added without upgrading the panel.
Extension cords and power strips used as permanent wiring are a frequent factor in house fires generally, not just older homes. An insurer looking at wiring age is asking a narrower question. Does this house have the kind of electrical system where a failure like this is more likely to go unnoticed until it's serious. A newer panel with modern breakers trips before a problem becomes a fire. An old fuse box or an ungrounded knob-and-tube circuit often doesn't give that same warning.
None of this means a house with older wiring is likely to catch fire. It means the margin for error is smaller, and the house depends more on the people living in it noticing warning signs like flickering lights, warm outlet covers, or a breaker that trips for no clear reason. An electrician can check for these conditions during a routine inspection. The same report that satisfies an insurer is useful to have regardless of who's offering the policy.
Before the deadline hits
Check whether the letter names an inspection report or just the wiring's age. If it's age alone, an electrician's report showing the panel and wiring are sound can change what the next insurer offers.
