The guy at the Mesa del Sol estate sale said his 1955 ranch had no insulation at all, just tar paper
I was poking around a sale over on the west side last weekend and got talking to the owner, who grew up in the house his dad built in 1955, and he said for the first 30 years they had nothing in the walls but tar paper and a prayer. He pulled a chunk of drywall off in the 80s and found a single layer of that black paper, which apparently was normal for tract homes going up around here back then. Anyone else ripped into an older Albuquerque place and found something like that, or is his story just nostalgia talking?