When home inspectors come to homes built in the 1970s and earlier we are looking at the main electrical panel for a variety of reasons. We carefully take the service cover off to see what the condition of the box, wires, disconnects and connections look like. It is a visual inspection looking for tell-tale signs of trouble. One of the big observations is to note the brand type. Most of the panels I see are the tried and true brands of Siemens, Square-D, Challenger, Eaton and the like. The concerning ones I’m looking for are the old-school fuse boxes, which are virtually non-existent today, Federal Pacific and Stab-Loc panels, and Zinsco panels. As I tell clients its not that every panel of this brand was a problem, just far too many became problems. And as I will offer in this brief article, a very DANGEROUS problem! Why did they become a problem? Design flaws initially and now in 2024 degradation due to wear and age.
A couple weeks back I came across the old-school fuse box from a bygone era. It is very rare for me to find one of these present in a home and certainly not active. In these panels a screw-in fuse and pull out blocks protect the electrical circuits from overloading. If we find fuse boxes in a house we pretty much know that knob and tube or ungrounded wiring is present.
The following sets of pictures offer you a view of the well-known Zinsco panel. The first one is one that appeared to be in good working condition. When I took the panel cover off the wiring was in virtually the same condition as when it was originally installed. In this situation I noted the panel type, some cursory information about the concerns with this panel type and age, and a recommendation for an electrician to evaluate. Bottomline, improvement recommendation.
A few months ago I was performing a pre-offer inspection. A buyer was inspecting the home before submitting their offer and entering into contract with the seller. They were preparing to submit a strong offer waiving the inspection contingency. As I performed the inspection I came to the detached garage joined to the main home by a causeway – the house and detached garage were separate structures that shared the same roof. The following pictures offer a much different image of the condition of the Zinsco panel. When I opened the service cover I was shocked and alarmed by what I saw! Carbon covered most of the wiring and melted plastic could be seen with the circuit breakers including the main feeds. I thought, “This can’t still be energized!” I pulled out my current tester and I was stunned. Holy smokes! This thing has been burning and won’t be long before we have a full on house fire!
The inspection was a real shocker and the first time I found the a real-time example of the Zinsco panel troubles. I showed both the real estate agent and client the discovery and recommended the listing agent be notified of an immediate life-safety issue in the house. Unfortunately recent rules in the industry made this warning and disclosure process very difficult.
An added challenge for household electrical panels is the degradation of the bus bars. The bus bars transport the electrical charge to the various wiring circuits in the house. When you flip on a lamp a small trickle of electricity moves across the copper (or aluminum) strip through the circuit breaker gate to the wire running through your wall, outlet receptacle, cord and into the bulb, until “Let there be light!” The oven, clothes dryer, dishwasher, vacuum, and iPhone charger all the do same. As years became decades these metal strips deteriorate and it is often recommended that a panel more than 40 years of age be replaced. Electrical panel replacements are also very expensive and what could have been done for $2,000 is now double that in many cases! The electrical panel is the one of the top components homeowners can expect to replace alongside the the roof, furnace, siding paint, and hot water tank.
If you have a house you house built since the mid-1980s don’t worry about these panel types. They dropped out of use by the early 1980s which is an interesting story for another time.
Double check the panel you have. If you have questions, concerns or would like a check-up home inspection to see how your home is performing? Please give me a call or email. I have many clients who invite me out for a check-up with a full or partial home inspection. I look things over as I do in my regular home inspections and can provide a verbal or full written report. The real prize and deal is the peace of mind and confidence all my clients have after our time together!
There is more information and photos I have provided on this topic in the past. Read the article “Problem Panels and Wiring” – https://wrightwayhomeinspection.com/problem-panels-and-wiring/
Numerous other household electrical articles are available by just clicking the “Electrical” tag in the menu.
If you enjoyed this article please consider sharing it!