Any, repeat, any reasonable insurance company that has any, repeat, any exp erience with old houses will accept K&T wiring as a matter of course. Our h ouse was built in 1890, and is by no means the oldest house in the neighbor hood. Visible from our front door are houses from 1850 through 1963, with t he preponderance built from about 1895 to about 1915. All but the 1960s hou se *will* have K&T wiring in them. The 1963 house will have ungrounded NM a nd thin-gauge grounded NM wire - no prize there either.
Our insurance company did send an inspector to check our wiring if only bec ause we have 'full historical replacement' insurance. But we got a clean bi ll and no issues or additions to our premium caused by vintage wiring still in use (lighting circuits only). We do have a 200A service, and extensive new wiring, by the way. Not as if we are Luddites.
Any company with such an exclusion would eliminate 2/3 of Cheltenham Townsh ip from coverage. Our oldest occupied house is from 1689.
Peter Wieck Melrose Park, PA