Is it possbile that some of a 1954 house would be concrete or drywall and some of the walls plaster? It appears this way to me as when I pulled back a piece of the paneling, the surface underneath is rough. When I removed a plate switch cover, I could see a rough material that appears to be about 1/4 thick. Yet in my bedroom, when I tried to drive a nail for a picture, I must have hit a stud or soemthing and got a few teeny layers of what seems to be plaster. Im befuddled.