Free tool
Knob and tube wiring assessment
9 questions about what you already know about the house. The result says how urgent your situation is, what it means and what to do next. Nothing is sent anywhere.
Nothing to open, test or measure. Answer from what you already know.
Answer the questions
Your result
Answer the 9 questions and your result appears here. Nothing is sent anywhere, and the questions only ask about what you already know.
How the result is decided
The rules run in a fixed order, and the first one that matches decides the result. The same answers always give the same result. The building type, the panel and any earlier rewire then add their own steps, such as planning a triple-decker floor by floor or asking a condo association which wiring is yours.
| If you said | The result |
|---|---|
| Heat, scorch marks or a burning smell | Stop using the affected circuit and call an electrician now. This outranks every other answer. |
| A pending purchase or sale, an insurer or an inspection report | Have the circuits traced before the date that matters to you. |
| Insulation planned, or a Mass Save assessment stopped it | Deal with the knob and tube first: Mass Save insulates an area only after a licensed electrician certifies it free of active knob and tube. |
| Insulation already in place over unchecked wiring | Have the attic wiring checked soon. |
| Fuses blowing often, or daily extension cords and space heaters | Get the overloaded circuits checked soon. |
| A remodel coming up | Plan the rewire with the remodel, while walls are open. |
| A permitted whole-house rewire already done | Confirm what is left with the permit record. |
| None of the above | Plan, not urgent. |
What this check cannot tell you
It cannot see inside walls, so it cannot say how much knob and tube a house has, whether a run is live or dead, or what condition it is in. Only tracing the circuits answers those questions.
It does not say whether a house is safe, and it does not predict what an insurer or lender will decide. Massachusetts publishes no single insurance rule for knob and tube, and homeowners report different terms from different carriers; the result is a way to plan the conversation with them.
Where the Massachusetts rules come from
The insulation result follows Mass Save's Home Energy Assessment standards, which treat active knob and tube as a barrier to insulation, and the City of Boston's guidance that inactive knob and tube does not block it. The remodel result follows the Massachusetts Electrical Code, 527 CMR 12.00, which also keeps new wiring uncovered until the inspector of wires has seen it. In Boston, a licensed contractor files the electrical permit with Inspectional Services; homeowners can't. Next: estimate the cost for your house.
Talk through your result
Send your result and the house details. Your assessment result is added to the request.
Call (617) 405-3599Decker Boston Knob and Tube361 Newbury Street, 5th Floor, Boston, MA 02115
office@deckerbostonknobandtube.com
Monday to Friday, 8 AM to 6 PM; Saturday and Sunday, 9 AM to 2 PM
Outside these hours, emergency calls only
Photos of the attic, the basement ceiling and the panel help most.