A homeowner in Albany Park called me last spring. The HELOC fell through because the appraiser flagged knob and tube wiring in the attic. They’d gotten three quotes for replacement: $7,800, $19,000, and $42,500. They wanted to know which one was real.
The honest answer is: probably all three were quoting different scopes of work, and at least one was hoping the homeowner wouldn’t notice.
Knob and tube replacement in Chicago has a wider price range than almost any other electrical project we do. A small condo with open walls and easy access can come in under $5,000. A full Victorian in Pilsen with plaster and three floors of finished work can cross $40,000 before drywall repair. The range exists because the wiring itself is rarely the expensive part. The access to the wiring is.
Here’s what actually drives the number, and what a real quote looks like.
Why insurance companies started flagging it
Knob and tube was the standard residential wiring method in Chicago from roughly 1880 through the late 1940s. It’s actually well-engineered for its era. Heavy copper conductors, ceramic insulators, and an intentional air gap to dissipate heat. When it was installed correctly and never touched, it can still pass an inspection on a circuit-by-circuit basis a hundred years later.
The problems are accumulated, not original. Over a century, knob and tube ages in three ways that matter: the rubberized insulation around the conductors hardens and cracks, especially near heat sources; previous owners have spliced into circuits with non-original methods, often without junction boxes; and modern insulation, blown-in cellulose or fiberglass batts, has been installed over the wiring in attics and walls, eliminating the air gap the original design depended on.
Most insurers in Illinois will not write a homeowners policy on a house with active knob and tube. The ones that will write it charge a surcharge, demand annual inspections, or exclude electrical fire coverage. That’s why most Chicago homeowners discover knob and tube during a sale or a refinance, not during ownership.
What “replacement” actually includes
A real knob and tube replacement isn’t just pulling old wire and shoving new wire in the same paths. It’s a full rewire. Here’s what that means.
Every branch circuit in the house gets a new run from the panel to its devices and fixtures. Romex, MC cable, or in Chicago specifically, EMT conduit where the AHJ requires it. The City of Chicago has historically required conduit on most residential branch circuit work, and not every electrician quotes it correctly.
Every receptacle, switch, and fixture box gets pulled and replaced with a modern grounded box. Knob and tube is a two-wire ungrounded system, so adding the third conductor and grounding all metal-bodied fixtures is part of the scope.
The panel almost always has to come along for the ride. A house wired for knob and tube usually still has a 60 or 100-amp service with a fuse panel or an early breaker panel. A full rewire is the right time to upgrade the service and the panel both. Pricing this work without the service upgrade is short-sighted.
The drywall and plaster repair is its own line item. This is the part that surprises homeowners. A clean fish-and-pull through a drywall ceiling means cuts and patches we can repair internally. Plaster walls, especially the lath-and-plaster you find in pre-1940 Chicago bungalows and Victorians, are a different conversation. Plaster cracks when you cut it. Patching is slower, more expensive, and rarely matches the original texture without a plasterer’s hand. We can include drywall repair in our scope. We don’t typically include plaster finish work.
Permits and inspections are mandatory. Multiple inspections, in fact, because rough-in and final are separate.
Real ranges in Chicago
I’ll give you ranges, not fixed numbers, because the truthful answer is the range. We’d quote your specific house off a walkthrough.
A small condo or coach house with limited knob and tube on a few circuits, open ceilings or unfinished basement access, gut-renovated kitchen with new wiring already in place: $4,000 to $8,000.
A 1,200 to 1,500 square foot Chicago bungalow, knob and tube throughout, drywall ceilings on the main floor and an unfinished attic where the runs are accessible, no plaster: $14,000 to $22,000.
A two-flat where both units are wired in knob and tube, panel upgrade required, mostly drywall with some plaster patches around windows and ceilings: $22,000 to $35,000.
A pre-1920s Victorian in Logan Square or Lincoln Park with three floors, plaster walls, ornate trim work, and finished basement: $35,000 to $55,000+.
These numbers include the rewire, the panel upgrade if needed, the permit, the inspections, and basic drywall patching where we cut. They generally do not include painting, plaster restoration, hardwood floor refinishing, or interior decoration. Those are trades you’ll bring in after.
The Bogleheads and Angi ranges you’ll see online ($4k to $40k) match what we see, which is why they get cited so often. The variance is real.
What makes a quote feel high or low
A bid that comes in significantly under the others almost always means one of three things.
The contractor is quoting a partial rewire, knob and tube only in some rooms, and leaving other circuits live. We don’t recommend partials. They almost never make insurance sense and the leftover knob and tube ages faster once it’s the only original wiring left in the system.
The contractor isn’t including the panel upgrade. If the existing service is 60 or 100 amps and the rewire is going to add modern dedicated circuits, the panel needs to grow. A bid without the service upgrade is incomplete.
The contractor isn’t including drywall or plaster repair. Some quote the rewire only and leave the patching to the homeowner. That’s a legitimate model but only if you’ve been told and have a plan for the patch work.
A bid that comes in high usually reflects either Chicago’s conduit requirements, plaster work that’s harder to access, or a bigger panel/service upgrade than the others quoted.
Why partial rewires usually fail the math
We get asked weekly whether we can rewire just the second floor, just the kitchen, or just the affected circuits. Almost always, we say no.
Insurance companies asking about knob and tube don’t grade on a curve. The presence of any active knob and tube circuit usually disqualifies the policy. So a partial rewire often doesn’t solve the insurance problem.
The labor cost of a partial isn’t proportional to the percentage of wiring replaced. The truck, the permit, the panel, the access, and the cleanup are largely fixed. A 40% rewire isn’t 40% of a full rewire’s cost. It’s closer to 70%.
The remaining knob and tube ages faster after a partial. With less of the original system carrying load, the older circuits may run more under the new draw patterns.
What we recommend looking for in a quote
A line for the rewire itself, broken out by floor or by circuit count.
A line for the panel upgrade, with the new service amperage and the panel brand named.
A line for permitting and inspections.
A line for drywall and plaster repair with the scope of patching defined. Painting almost always excluded.
A schedule, in calendar weeks, with the inspections placed.
If your quote doesn’t have those line items, you can’t compare it.
Work with a licensed Chicago electrician
Knob and tube rewiring is one of the more disruptive projects in residential electrical, and it deserves a contractor who’s done a few hundred of them in Chicago housing stock. Star Victory Electric has been handling residential, commercial, and industrial electrical work across Chicagoland since 1992. We pull every permit, schedule every inspection, and quote off a walkthrough so the number you see is the number we stand behind. Licensed, bonded, and insured. Request a walkthrough at starvictoryelectric.com or call (773) 234-0172.
