Knob-and-tube wiring: the credit-request playbook for buyers
Knob-and-tube wiring was the residential standard from roughly 1880 to 1940. It is grounded only at the panel, not at outlets, and the insulation breaks down with heat. Most insurance carriers will not write coverage on active K&T. If your inspector found it, the question is not whether to negotiate, only how much.
What this finding actually is
K&T uses ceramic knobs to support hot and neutral wires running separately, with porcelain tubes through joists. The system is fundamentally safe when undisturbed and dry, but most homes have decades of attic insulation laid over it, additions tied into it, and connections that have heated and cooled through a thousand load cycles. Insurers treat the system as elevated fire risk regardless of condition.
Replacement means running new Romex through walls and ceilings, replacing all outlets and switches with grounded equivalents, and patching drywall at every access point. In a typical 1,500 to 2,500 sq ft home, this is two to four weeks of work for a small crew.
Why it is a credit conversation, not a fix-it conversation
The primary leverage is insurance. Most major carriers either decline outright, require full removal within 30 to 90 days of binding, or surcharge by 30% to 50%. Buyers who do not negotiate this either pay the rewire cost themselves or pay surcharged premiums in perpetuity.
Lenders also occasionally flag K&T at appraisal, especially FHA and VA loans, requiring remediation as a closing condition. The cost moves with home size; the leverage is the same in any home that has it.
How to confirm what your inspector found
Inspectors look for ceramic knobs and tubes in the attic, basement, and crawlspace. The inspector report will say knob and tube, K&T, or open wiring. Confirm whether the K&T is active (energized) or abandoned: abandoned K&T that has been bypassed is not an insurance issue.
The bullet to put in your credit-request letter
Paste this into the bullet list in your credit-request letter and replace the bracketed fields with your own. The structure is what makes it work: finding, page citation, cost range with source, requested credit.
Active knob-and-tube wiring documented in attic and partial second floor (inspection page X). Cost range $8,000 to $20,000 for full rewire including drywall patching and new fixtures. Insurance and lender implications attached. Requested credit: $X.
How much to actually ask for
Ask for 70% to 80% of the rewire estimate. Sellers who counter usually counter at 50%, so anchor higher. Attach a homeowner-insurance quote that shows the K&T surcharge or exclusion, which makes the cost real to the seller rather than theoretical.
Questions buyers ask before they negotiate
How do I know if my home has K&T?
Inspector access to the attic and basement is enough. K&T is visually unmistakable: ceramic knobs supporting cloth-wrapped wires. If the inspector wrote it in the report, the finding is reliable.
Is partial rewire (just the active runs) enough for insurance?
Usually. Insurers care about energized K&T, not abandoned legacy wiring. A rewire that energizes new Romex and de-energizes K&T closes the underwriting issue even if the old wires stay in place.
Can I just buy a different insurance policy that allows K&T?
Specialty surplus-lines carriers will write it, usually at 50% to 100% premium increase. That extra premium is real money: factor it into your hold cost and use it in the credit negotiation.