attic vs mansard

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. 

mansard

noun
  • The upper storey of a building, surrounded by such a roof 

  • A mansard roof 

adj
  • having two slopes on each side, the lower being steeper than the upper 

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