Guides

Knob and tube wiring guides

Straight answers about the oldest wiring in Boston-area houses from Decker Boston Knob and Tube: how it works, when it becomes a problem, what the Massachusetts Electrical Code and Mass Save require, how insurers and buyers treat it, and what replacing it involves and costs. Guides are grouped by the service they lead to.

Start with the question in front of you. Each guide links to the next decision.

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The background first: what knob and tube is, how a replacement runs from circuit map to closed walls, what it costs around Boston, and how the Boston permit works.

LearnWhat is knob and tube wiring, and what does it mean for a Boston house?How the oldest wiring in Boston-area houses was built, what it still does well, where it goes wrong, and how Massachusetts rules, insurers and Mass Save shape what you do next.LearnHow does a Boston electrical permit for rewiring work?Every knob and tube rewire in Boston runs through one permit office, one fee formula and two state rules about when walls can close. Here is the sequence from filing to final sign-off.Decision GuideHow do you compare knob and tube rewiring quotes?Two rewiring quotes for the same Boston-area house can be thousands apart and both be honest, because they describe different jobs. Lining them up on the same points shows which job each one is.LearnHow is knob and tube wiring replaced?A rewire runs in an order the code partly sets. Each stage depends on the one before it, and knowing the order explains most of the schedule and the price.Cost GuideHow much does knob and tube replacement cost in Boston?The range Boston-area owners budget with, the handful of things that push a house toward either end, and the public figures sitting inside every price.

Knob and Tube Inspection

Questions that start with someone else's finding: a home inspector, an insurer, a buyer or a seller, and what Massachusetts law actually says about old wiring.

Knob and Tube Inspection in Boston →

Decision GuideShould you buy a house with knob and tube wiring?Plenty of good Boston-area houses still have some knob and tube. The ones that turn into problems are the ones bought without knowing how much is live, what it costs and whether it can be insured on time.LearnHow do you identify knob and tube wiring?A field guide for owners and buyers: where to look in a Boston-area house, what each part of the system looks like, what gets mistaken for it, and where looking stops being enough.LearnIs knob and tube wiring dangerous?Why the same wiring can be sound in one Boston attic and a fire risk in the next, which warning signs need a call this week, and what an inspection can and can't settle.LearnIs knob and tube wiring legal in Massachusetts?Existing knob and tube can stay, new work can't make it worse, and only licensed electricians can touch it for hire. A plain reading of the state rules that apply.LearnCan you insure a house with knob and tube wiring in Massachusetts?No Massachusetts law makes a carrier refuse old wiring, yet the question decides many closings and renewals. Here is how underwriting treats it and what paperwork moves the conversation.Decision GuideCan you sell a house with knob and tube wiring in Massachusetts?The wiring won't stop a sale, but it will shape the buyer's inspection, their insurance quote and the price talk. Three ways to get ahead of it, and what each costs you in time.

Knob and Tube Removal

How live and dead knob and tube are told apart, and why a run cut at the panel isn't always out of service.

Knob and Tube Removal in Boston →

LearnHow can you tell if knob and tube wiring is live?A cut end in the attic, a dusty run in the basement, a previous owner's promise: none of them proves the old wiring is dead. What it takes to know, and why the proof should be on paper.

Whole-House Rewiring

What a whole-house rewire involves for the people living in it, the warning signs that point to one, and why old circuits can't carry modern loads.

Whole-House Rewiring in Boston →

LearnHow many amps can knob and tube handle?Search for one number and you'll find several, none of which describes your house. The safe load on an old circuit comes from its wire, its surroundings and the fuse that protects it.LearnCan you live in a house while rewiring?Most households stay put through a knob and tube rewire. What makes that comfortable is planning the shutdowns, the dust and the heat before the first circuit goes dark.Decision GuideWhat are the signs your house needs rewiring?Old houses rarely announce bad wiring with one clear symptom. Sorting what you notice into urgent, worth planning for and not a symptom at all tells you what to do next.

Partial Replacement

Houses where earlier owners replaced some circuits and left others, and how to decide between finishing the job and replacing everything.

Partial Replacement in Boston →

LearnWhat happens when knob and tube is mixed with Romex?Decades of kitchen remodels and added outlets can leave an old house with new cable spliced onto its original circuits. The cable isn't the weak point. The places where it meets the old wiring are.Decision GuideShould you replace part of your knob and tube or all of it?Repair, partial replacement and a whole-house rewire answer different problems. The circuit map, the reason you're acting now and your plans for the walls decide which one fits.

Insulation Barrier Work

The help available when knob and tube is what stands between a house and its Mass Save insulation.

Insulation Barrier Work in Boston →

Decision GuideAre there grants for knob and tube removal in Massachusetts?True grants are rare. The real help runs through Mass Save's insulation programs and a few city and state loans, and the order you apply in matters as much as which one you pick.

Plaster Wall Rewiring

Rewiring through plaster and lath, including lead paint rules for houses built before 1978 and design review in Boston's historic districts.

Plaster Wall Rewiring in Boston →

LearnDoes knob and tube wiring have asbestos?Three old-house materials can sit right where a rewire goes: the wire's own covering, the paint on the plaster, and the fill in the attic. Here is what is known, what has to be tested, and how each changes the job.LearnWhat changes when you rewire a historic home in Boston?District commissions care about what the street can see, so most of a rewire never reaches them. The parts that do are the meter, the mast and the conduit, and inside, the plaster and trim are yours to protect.

Triple-Deckers and Multi-Family

Wiring questions specific to triple-deckers, condos and other buildings with more than one household.

Triple-Deckers and Multi-Family in Boston →

Fuse Box and Panel Upgrades

What a fuse box or panel upgrade costs around Boston and what it does, and doesn't do, about the knob and tube behind the walls.

Fuse Box and Panel Upgrades in Boston →

Decision GuideDoes a panel upgrade remove knob and tube?Swapping a fuse box for breakers changes what protects the circuits, not the wire inside the walls. Here is what that means for code, insurers, Mass Save and your budget.Cost GuideHow much does an electrical panel upgrade cost in Boston?What Boston-area owners budget to replace a fuse box or small service, why quotes for the same house can be thousands apart, and which parts of the price come from public rules.

Ungrounded Outlet Upgrades

Two-prong outlets, ground-fault and arc-fault protection, and what Massachusetts requires on old circuits.

Ungrounded Outlet Upgrades in Boston →

LearnCan you put AFCI and GFCI protection on knob and tube?Ground-fault and arc-fault devices each watch for one kind of failure. On a two-wire circuit they can add real protection, but they don't add a ground and they don't make old wire new.

Cloth Wiring Replacement

How cloth-insulated cable from the middle of the last century differs from knob and tube, and when it needs replacing too.

Cloth Wiring Replacement in Boston →

LearnWhat is the difference between knob and tube and cloth wiring?Four generations of wiring can share one Boston-area house. Here is how each one is put together, what it lacks, and why an electrician treats them differently.

Rewiring During a Remodel

Using open walls during a kitchen, bath or attic project to deal with the wiring behind them.

Rewiring During a Remodel in Boston →

Ask about your house

Reading is a start; a circuit map answers the question for your own house. Call or send the form.

Call (617) 405-3599

Decker Boston Knob and Tube
361 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.