"Buck Turgidson" wrote:

I have seen this mentioned in reference to blowing in cellulose insulation,
and how it is a fire hazard. What exactly is this type of wiring? I have a
house built in 1961, and as far as I know, it just has the cable with fabric
sheathing.


The first wiring system used in houses. Insulated wires run on
insulators (the knob) and through short insulated tubes when the wire
has to be run through a wall stud or joist.

Houses were wired up with 2 circuits, usually 30 amps, 3 wire 220v, and
#10 wire, 2 screw in fuses.

K&T wiring is very safe, the workmanship required is very high to do
right, and it was done right decades ago.

Where it is unsafe, is when people expand the wiring buy just adding on
ad hoc, for example, BX that is just connected to the hot and neutral,
since there is no ground in a K&T system.

And way, way past the original limits.