attic vs rooftop

attic

noun
  • The space, often unfinished and with sloped walls, directly below the roof in the uppermost part of a house or other building, generally used for storage or habitation. 

  • A person's head or brain. 

rooftop

noun
  • The area atop a roof. 

  • The top layer of a roof; the material covering or composing a roof. 

How often have the words attic and rooftop occurred in a corpus of books? (source: Google Ngram Viewer )