Straight answers to fair questions.
How do I know if my house has knob and tube?
Look in the basement ceiling and the attic: single wires (not cables) running through white porcelain knobs and tubes are the giveaway. Houses built before 1950 are the candidates. Visible knob and tube is not always live, and live knob and tube is not always visible, which is why tracing beats guessing.
Is knob and tube illegal?
Existing, intact, unmodified knob and tube is generally allowed to remain under the code. That is a narrower safe harbor than it sounds: it may not be buried in insulation, extended, or spliced onto, and decades of renovations usually broke those conditions long ago. Legal or not, insurers flag it, which is what forces most replacements.
What does replacement cost?
Full rewires run $8 to $17 per square foot in this county, so a typical 1,500 to 2,000 square foot older home lands between $12,000 and $18,000, plus $1,500 to $4,000 for the panel upgrade most of these houses also need. Partial, per-circuit rescues cost less. Our cost page publishes the whole table with worked examples.
How long does a rewire take?
The physical work runs four to eight working days for a typical house, with power staying on outside the circuits being replaced. The county permit is a flat $30 filed online, with one to three weeks of processing that scheduling proceeds against. From first call to passed inspection, plan on three to five weeks.
Do you tear up the plaster walls?
Mostly no. Old-house rewiring is a fishing trade: attic and basement access, small targeted openings, and wire pulled through existing cavities. Patching happens and gets quoted honestly as its own line. Nobody should promise you zero wall openings, and nobody should leave you with a demolition site either.
Can I sell my house without replacing the knob and tube?
You can list it, but the buyer’s insurer will flag it, and the negotiation lands on the same three options every time: rewire before settlement, adjust the price, or escrow the work. Sellers who fix it before listing keep the leverage. Our selling and insurance page walks the whole sequence.
Who actually does the work?
Licensed Maryland master electricians. Cecil County requires no separate county license; the $30 electrical permit is filed against the state master license through the county’s online portal, and the county inspection closes out every job. The passed inspection is your proof for insurers and future buyers.
What should I look for when comparing rewiring bids?
Three things: per-circuit itemization so bids can be compared at all, patching and permit named in the scope, and published reference pricing you can hold the bid against. A lump-sum number missing those is not a comparable bid. Ours itemizes against the table on the cost page on every quote.
Something we didn’t cover? Call (443) 993-5051 or start with the quote form. Town-specific questions are answered on each area page.