Short answer
Yes. Knob-and-tube wiring does not stop a sale in Pennsylvania, but disclose it on the seller disclosure statement if you know about it. Buyers may ask for an electrician's evaluation, a credit or a lower price, and some municipalities require electrical certifications at resale. Mortgage buyers can run into insurance or lender questions.
Disclosure
Pennsylvania's Seller Disclosure Law lists the electrical system as a subject for the property disclosure statement. If you know the house has knob-and-tube wiring, or know that parts of it were never updated, say so. You are not required to investigate, so you do not need an electrician to open walls.
The law also notes that something near or beyond its normal useful life is not by itself a material defect. But wiring that creates an unreasonable risk to people on the property can be one. If an inspector or electrician told you it was unsafe, that is a known problem.
What buyers and towns do
A buyer's inspector will often flag old wiring. The buyer may ask for a licensed electrician's report, a credit or a price cut, or may walk. Some municipalities add their own rules at resale. Bensalem Township, for example, requires a certificate from an approved electrical underwriter showing the electrical service panel complies with the current National Electrical Code before it will issue a resale occupancy permit. That certificate relates to the panel, and your township may ask for more.
Call your township building office early to learn what applies.
A buyer may also ask that you hire a licensed electrician to evaluate the system. Ask for a written report, so the discussion rests on facts.
Insurance and financing
This answer did not review insurance or lender policies. Some insurers and lenders ask questions about older wiring, and a buyer who needs a mortgage may have to satisfy both. That is one reason these houses sell to cash buyers more often than to financed buyers.
If you plan to list, ask an agent how local buyers have reacted to older wiring and ask a licensed electrician for a written estimate to replace it. Compare the estimate to the discount a buyer asks for.
Fix first or sell as-is
Rewiring is disruptive and expensive, and it can reveal other issues. This answer does not quote a cost, because we have no verified source for a typical Pennsylvania figure. If you have the budget and time, upgrading can widen your pool of buyers. If you do not, selling as-is can be the better choice.
If you do repair, keep permits and the electrician's invoice and disclose what was done.
Also check any permit history. Unpermitted electrical work on top of old wiring is a separate problem that you would need to disclose if you know about it.
Where Kaizen fits
Kaizen Home Buyers buys as-is, so you do not need to rewire. We make a cash offer within 24 hours, close typically in 14 to 30 days or on your date, and charge no agent commission. Call 267-329-0084 and tell us what you know about the wiring.