Old Wiring in an Old House: Service, Panels and the Insurance Problem

Electrical findings get a line or two in an inspection report and deserve considerably more attention than that, because they are one of the few categories that can independently stop a sale. Not by failing an inspection — there is no such thing — but by an insurer declining to write a policy, which means the lender will not fund, which means there is no closing.

Start with the service, not the wiring

The first question is how much electricity the house can draw, and it is answered at the meter and the main breaker.

60 amps is the old standard and is inadequate for a modern household. A house still on 60-amp service is a house that needs an upgrade, and insurers frequently say so.
100 amps is workable for a modest house with gas heat and cooking and no large loads.
200 amps is the practical current standard, and it is what you want if there is any prospect of electric heat, a heat pump, central air conditioning, an induction range or a car charger.

This matters more every year. The whole direction of Massachusetts energy policy is electrification — heat pumps, induction, vehicle charging — and a house on 100-amp service will need an upgrade before it can take much of that. Energy efficiency: what pays back covers the incentives; the service panel is the constraint nobody mentions when they are selling you a heat pump.

The panels that cause trouble by name

Two brands come up repeatedly in older Massachusetts houses and are worth recognising in a photograph:

Federal Pacific Electric Stab-Lok panels, common from the late 1950s into the early 1980s, which have a long-documented history of concern about breakers failing to trip.
Zinsco panels, from a similar era, with a similar reputation.

Neither is a code violation by virtue of existing, and neither is automatically a catastrophe. What both are is a finding that many insurers and inspectors flag, and that a licensed electrician should evaluate rather than a blog post. Replacement of a panel is defined, quotable work; get a written number during your inspection period and treat it like any other repair item.

Also look for a fuse box rather than breakers — workable but dated, and another thing an insurer will ask about — and for a panel that is obviously full, with tandem breakers doubled up in every slot.

Knob-and-tube, in proportion

The famous one. Knob-and-tube is the original wiring method in houses of a certain age here — conductors run separately, supported by ceramic knobs and passing through ceramic tubes.

The honest position: intact knob-and-tube, undisturbed, not overloaded and not buried in insulation, is not necessarily an emergency. Three things make it one.

1.It has no ground. Two-prong outlets throughout, and no grounding path for modern electronics or for the safety devices that depend on one.
2.It has been covered with insulation. This is the real hazard and it is extremely common, because the wiring was designed to dissipate heat into open air and somebody later blew insulation into the wall cavity or laid batts over it in the attic. Well-meant weatherisation is how a tolerable situation becomes a dangerous one.
3.It has been amateurishly extended. Sixty years of somebody's uncle adding an outlet. Junctions outside boxes, modern cable spliced to cloth-insulated conductors, fabric sheathing that crumbles when touched.

The practical consequence in a transaction is usually the insurance one: many carriers decline knob-and-tube outright and others require it removed within a set period after closing. That is the question to ask, in writing, before your contingency expires.

Aluminium branch wiring

Less famous and worth knowing. Houses wired roughly between the mid-1960s and mid-1970s sometimes have aluminium branch circuit wiring, which expands and contracts differently from copper and can loosen at connections over time.

It is not a demolition-grade finding — there are recognised remediation methods using approved connectors at devices and junctions, performed by an electrician. But it is another item insurers ask about, and it is easy to miss because it looks like ordinary cable unless somebody reads the marking.

The insurance conversation, which is the one that has a deadline

This is the single most important practical point on this page.

Before your inspection contingency expires, call your insurance agent, describe what the inspector found — service size, panel brand, wiring type — and get a written answer to three questions: will you write this property, at what premium, and what do you require to be corrected first. Carriers differ enormously on all three.

An answer that arrives after the contingency has gone is not an answer you can act on, and this is the category where a declination is most likely. The home insurance guide covers how the rest of the policy fits together, and oil tanks is the other finding with the same uninsurability trap.

What good work looks like

Electrical work in Massachusetts requires a licensed electrician and an electrical permit, inspected by the municipal wiring inspector. That is not a formality — it is the paper trail that proves the work was done properly, and its absence is what makes unpermitted improvements a discount rather than an upgrade.

So ask for permits. A house with a recently upgraded service and a permit on file is a house where somebody did it correctly. A new-looking panel with no permit history raises the question of what else is not recorded, which is the theme of zoning and building permits.

A buyer's sequence

1.Note the service size from the panel, and photograph the panel label.
2.Ask the inspector directly about grounding, about the panel brand, and about whether knob-and-tube is present and whether it is in contact with insulation.
3.Get an electrician in during the inspection period if anything above is present — they will quote what an inspector cannot.
4.Call the insurer with the specifics and get the answer in writing.
5.Ask for permit history at the building department.
6.Then negotiate on real numbers. Negotiating beyond price covers how that conversation runs.

A seller's version

If your house is on 60-amp service, has a panel with a reputation, or has live knob-and-tube, you already know what your buyer's inspector is going to say. Two options and both are legitimate: correct it and be paid for a house that is insurable, or price it and be ready with a quote so the finding costs you the quote rather than the negotiation.

What is not an option is being surprised by it in week three, which is the version that costs the most.