がいし引き工事
Meanings
1
knob-and-tube wiring; insulator wiring
Refers to an older electrical wiring method where wires are run along surfaces using ceramic insulators (knobs and tubes). Primarily a technical term in electrical engineering and construction.
In old houses, knob-and-tube wiring sometimes still remains.
Knob-and-tube wiring is considered less safe compared to modern wiring methods.