knob and tube

[Bruce A. King]

Is this a version of knob and tube?

The wires are insulated.

[Jeffrey R. Pope]

Yep. That would be an "open-conductor support."

[Michael Larson]

Jeff,

How much of an issue is the insulation packed around it?
I would think it would contribute to conductor overheating.

[Jeffrey R. Pope]

It's not allowed. I would say that it's a "substantial" issue which should be corrected.

394.12 Uses Not Permitted.

Concealed knob-and-tube wiring shall not be used in the following:

(5) Hollow spaces of walls, ceilings, and attics where such spaces are insulated by loose, rolled, or foamed-inplace insulating material that envelops the conductors

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