A knob-and-tube removal letter is a written statement from the licensed electrical contractor describing which original circuits were replaced or disconnected, and what remains. Insurers ask for it as proof that active knob and tube is no longer in service. It is strongest when it matches the permit, the inspection record and the work actually done.
Philly Knob & Tube organizes knob-and-tube removal and replacement for Philadelphia properties through licensed and insured electrical contractors. Whether a given contractor will issue a letter, and in what form, depends on that contractor and on what the work and inspections can support, so treat the letter as something to agree on before work starts rather than an automatic extra. This guide explains what the document should contain and how to keep it honest. For why carriers ask in the first place, see the homeowners insurance guide.
Who Issues Documentation and What It Says
The document carriers usually mean is a letter from the electrical contractor that held the permit and did the work. In Philadelphia that contractor must be licensed with L&I, with insurance on file, so the letter ties the statement to a business the city has already vetted for electrical work. A note from a handyman, a general contractor or a home inspector does not carry the same weight, because none of them is the party responsible for the circuits.
A useful letter is plain and specific. It should include:
- The contractor’s name, license number, address and contact information, on letterhead.
- The property address and, for a two-to-four-unit building, which units or common areas the work covered.
- The dates of the work and the electrical permit number.
- A description of the scope by circuit or area: for example, “replaced the knob-and-tube branch circuits serving the second floor bedrooms, hall and bath with new grounded cable from a new panel.”
- What happened to the old wiring: removed where accessible, or disconnected at both the source and the last device and left in place.
- Anything outside the scope or not observed.
- A signature and date.
What the letter should not do is offer opinions it cannot back up. “The house is now safe” or “the electrical system is fully up to code” are judgments about parts of the building no one examined. Underwriters tend to give more weight to a narrow statement they can rely on than to a sweeping one that sounds like marketing.
Circuit Extent and Limits of Certification
The hardest sentence in any removal letter is the one about what is left. Most knob-and-tube jobs in plaster houses do not tear every old conductor out of the walls. New cable is fished through existing cavities, and the original runs are disconnected and abandoned in place because pulling them out would mean opening far more plaster than the rewire itself. That is normal practice, and it is the reason the letter has to be careful.
Abandoned wiring is not the same as removed wiring, and the letter should say which is which. Wire that has been cut at the panel and at the last outlet, and confirmed dead, can no longer carry current. If your carrier asks whether knob and tube is “present,” that answer is still yes. If it asks whether any is “in service,” the answer may be no. The active versus abandoned guide explains why disconnection at both ends matters: a run cut only at the panel can still be connected to something live through a splice further along.
Mixed circuits create a second trap. If a previous remodel spliced modern cable into an original run, an electrician replacing “the knob and tube” in one area may leave an old feed upstream unless the scope traces the whole circuit. The mixed wiring guide covers how those splices hide. A letter that says “all knob and tube on the first floor replaced” when a first-floor outlet still draws through an old attic run is a problem waiting for the next inspector.
The honest phrasing tends to look like this: which circuits were traced and replaced, which old conductors were disconnected and confirmed dead, and which areas could not be observed without opening finishes. That last item is not a weakness in the letter. It is what makes the rest of it credible.
Permits and Final Inspection Records
The letter tells an underwriter what was done. The permit and inspection records show it was done lawfully and checked by someone independent.
In Philadelphia, replacing branch wiring requires an electrical permit from L&I, applied for through eCLIPSE by the licensed contractor or another authorized agent. The owner or the owner’s agent hires a licensed third-party electrical inspection agency to perform the inspections; L&I does not send its own electrical inspector for this. Rough-in work is inspected before walls and ceilings are closed, and the finished installation gets a final inspection. The permit guide explains the permit types, and the final inspection guide covers the closeout.
Keep these records together with the letter:
| Record | Where it comes from | What it proves to a carrier |
|---|---|---|
| Electrical permit | L&I, through eCLIPSE | The work was filed by a licensed contractor with a described scope |
| Rough-in inspection approval | The third-party inspection agency | Concealed wiring was checked before it was covered |
| Final inspection approval | The third-party inspection agency | The finished work passed |
| Contractor’s proposal and final invoice | The electrical contractor | What was priced and what was billed, circuit by circuit |
| Photos taken during the work | The contractor or the owner | New cable, cut-and-capped old runs, the panel before and after |
The permit’s scope description matters more than people expect. If the permit says “replace two circuits” and the letter says “whole-house rewire,” a careful underwriter will notice. Ask the contractor what the permit application will say before it is filed.
Making the Paperwork Match the Work
Most documentation problems come from documents written at different times by different people for different purposes. The proposal is written before anyone opens a wall. The permit is filed early. The invoice reflects change orders. The letter is written last, sometimes weeks later. If each one describes the job slightly differently, the set looks inconsistent even when the work is fine.
A few habits prevent that. Agree on the circuit names at the start, using the same labels the assessment used, and carry them through the proposal, the panel directory and the letter. When a change order adds or removes a circuit, ask for the change to be written down in the same terms. If the scope grows partway through, find out whether the permit needs to be revised. And ask for the letter to reference the permit number and the inspection dates, so a reader can connect them without phoning anyone.
The panel itself is part of the record. A new panel with a clear, typed directory naming each circuit’s rooms lets an insurer inspector, a buyer’s electrician or the next owner see at a glance what was replaced. A panel replacement on its own does not remove knob and tube from the branch circuits, which is exactly why the directory and the letter need to agree about which circuits are new.
When the Work Was Done Years Ago
A common version of this problem has no fresh job behind it. A previous owner had the house rewired, a seller’s listing said “updated electric,” and now a carrier wants a letter nobody ever wrote. The contractor who did the work may be retired or impossible to identify.
Start by gathering what exists: closing documents, the seller’s disclosure, any old invoices left in a kitchen drawer, the panel’s age and labeling. If the original contractor can be found, it may be willing to write a letter describing work it did, but only from its own records. It cannot honestly certify the present condition of a house it has not seen in years.
When the history cannot be reconstructed, the practical route is a new electrical assessment by a licensed contractor that traces the circuits as they are today. The result is a condition statement rather than a completion letter: it says what was found active, what was found disconnected and what could not be observed. Many carriers accept that kind of current-condition report, though only your insurer can say whether it will. The inspection checklist lists what such a visit should cover, and the same records later help when you sell, as the selling guide and the post on organizing rewire records explain.
Confirming What the Insurer Actually Requires
Before the job is scoped, ask your carrier for its documentation requirement in writing. Some want only a letter. Some have their own form that the electrician must complete. Some ask for photos, a copy of the permit or the final inspection approval. A few specify wording, such as a statement that “no active knob-and-tube wiring remains,” which the contractor can only sign if the scope is designed to make it true.
Find out who the document must come from, whether a license number is required, where to send it and whether it must arrive by a date. If there is a date, the deadline guide covers how to plan around it. Then give that written requirement to the contractor when you request a removal estimate, so the scope, the permit description and the eventual letter are all built toward the same sentence. If the carrier’s wording asks for something the work cannot support, it is better to learn that before work starts than after the walls are patched. The quote comparison guide shows how to check that each bid includes the documentation you need, and the contact page is where to send the carrier’s request along with your project details.
