When I worked framing houses in the 70s it was standard practice to cover the subfloor with 3/4 particle board after the walls were up. Kinda dumb looking back on it. About half the nails you tried to drive would ricochet across the room. Wonder no one lost an eye. We didn’t bother with things like safety glasses.
Yep, no air nailers back then , all hand drive and that stuff is HARD. Carpet was the rage in the 70's, that pale green shag was the bomb..........back then.
