I was reading an old code book from the 1950s and the wire sizes were totally different

I picked up a vintage NEC handbook from 1957 at a yard sale last weekend. It said a 60-amp service for a house could use No. 6 rubber-covered wire. That's way smaller than what we use now for the same load. It really shows how much insulation and conductor materials have improved over the years. Has anyone else come across old specs that seem crazy by today's standards?

3 comments

3 Comments

robin4892mo agoMost Upvoted

Actually, I disagree that materials got better. Maybe the old specs were right and we're just wasting copper now. That No. 6 wire worked fine for decades in millions of houses without burning them down. Modern codes add huge safety margins that drive up costs for no real gain. It feels like change for the sake of change sometimes.

brianhernandez2mo ago

Yeah but @robin489, if the old stuff was so perfect, why did we keep having electrical fires? I get the cost thing, it sucks, but those safety margins came from somewhere. Probably from a bunch of houses that did burn down. Maybe the code guys are just covering their butts, but I'd rather pay a bit more for copper than have my insurance company tell me my place is a known fire risk.

jackson.jenny1mo ago

Wait, didn't your buddy's place almost go up last year from old wiring? My friend Sarah bought this cute 1920s bungalow and thought she was being smart by keeping the original cloth wiring. Said it was "vintage charm" or whatever. A year later her electrician showed her where the insulation was literally crumbling off inside the walls, just bare copper touching wood. Cost her triple what new wire would have been because they had to tear out half the plaster. She tells everyone now that old wire isn't "vintage" it's just "old." I'd rather pay for copper now than for drywall later man.