Knob and tube is not automatically dangerous. It becomes a problem when it has been buried in insulation, spliced into without a box, or asked to carry loads it was never built for. Usually what forces the job is an insurer.
The original installation was competent for the loads of its day. It has no ground conductor, it relies on air around the conductors to shed heat, and it was designed for lighting and a few outlets. None of that is dangerous on its own.
What makes it dangerous is a century of alterations. Insulation blown into a ceiling removes the air the wiring needs. Junctions made without a box and buried in a wall cannot be inspected.
Modern loads on circuits sized for a lamp are the third. An electrical safety inspection tells you which of the three you have, and thermal imaging finds the connections already running warm.
It also cannot be extended. Adding a circuit to knob and tube is not permitted, so any new work has to be separated from it, which is why a small job sometimes turns into a bigger conversation about whole home rewiring.
Fresh install
How it runs
Knob and tube replacement in Buffalo, four steps
Find out how much is live
Not all knob and tube in a house is still connected. We trace what is actually carrying current, because that is what an insurer cares about and what sets the price.
Full or partial, both quoted
You get the whole-house number and the partial number, with what each one leaves behind stated plainly.
Staged around the house
Work is sequenced so you keep power where you need it. Access decides the order more than anything else.
Inspection and certificate
Booked by us. The certificate is what your insurer will ask to see, so it comes to you rather than staying in our file.
Cost, and what forces it
The insurer decides knob and tube timing, not the fault
Most people do not call about knob and tube because something went wrong.
Full removal on a detached 1,500 to 2,500 sq ft home runs $12,000 to $20,000, and materially less when walls are already open for a renovation.
Aluminum branch wiring is a different problem people often confuse with this one, and it has a much cheaper answer. If your home has that instead, aluminum wiring replacement sets out what pigtailing does and when it is sufficient.
Where the panel is old too, an electrical panel upgrade is usually scheduled alongside rather than separately, and the permit covers both rather than two visits.
Full removal on a detached 1,500 to 2,500 sq ft home runs $12,000 to $20,000, and less where walls are already open for a renovation. Access drives the price more than floor area does. Figures are example ranges until we have seen the house.
Many will not write a new policy on a home with live knob and tube, and others attach a removal condition of 30, 60 or 90 days to a purchase. Ask your insurer for their requirement in writing before you price the work, because it decides whether partial removal is enough.
Often, yes. Where only some circuits are still live, replacing those and separating them from everything else satisfies many insurers at a fraction of a full rewire. We quote both.
No, and a good crew opens as few as possible. Attics, basements and closets carry most of the new runs. Where plaster has to come out we tell you which walls before we start, not afterwards.
New work cannot be extended from knob and tube, so anything new is run separately. That is allowed and is often the sensible first step, but it does not remove the insurer question.
No. That wiring relies on air around it to shed heat, and burying it in insulation is one of the few genuinely dangerous things you can do with it. Insulation work forces the question.
Find out how much knob and tube is live in Buffalo
An inspection tells you what is still carrying current, which is what your insurer is asking about. You get full and partial removal priced separately.
