Old house wiring: what cloth-covered, ungrounded and two-prong actually mean for you
Difficultymedium
Cloth-covered NM from the 1940s and 50s is usually fine if the insulation is not crumbling; the problem is no ground. Options for two-prong outlets, in code order: run a ground wire to the panel or a grounded point; install a GFCI receptacle labelled "No Equipment Ground" (legal, protects people, does not protect surge protectors); or rewire. Never just swap in a three-prong without a ground; a tester will show "open ground" and surge strips will not work.
Knob and tube: not inherently dangerous if untouched, but it cannot be insulated over and most insurers want it gone.
#old-house#ungrounded#two-prong#knob-and-tube#electrical
20
💬 4 comments
4 comments
Log in or sign up to join the discussion.
Can confirm, the cheap part is the one that fails. Replaced mine twice before reading this.
Unplug it. Always. Takes two seconds and the worst case otherwise is a trip to the ER.
This is the kind of post that makes this place worth it.
Unplug it. Always. Takes two seconds and the worst case otherwise is a trip to the ER.