I’m currently designing a keep for my players to explore. It will be a ruined keep, taken over by an evil cult. But to start off the design, I am looking at how it would have been designed in its prime. Here are some rooms I’ve thought of when creating the layout.

Military function

  • Armory
  • Smithy
  • Fletcher
  • Training room
  • Lookout posts
  • Infirmary/Hospital wing
  • Gatehouse
  • Barbican
  • Place of Arms
  • Commander quarters
  • Guard bunks

Every day operation

  • Great hall (mess hall)
  • Steward’s Office
  • Clerks/Tax assessors/Scribes Office
  • Kitchen
  • Distillery
  • Scullery
  • Larder/Storeroom/Cellar/Ice House
  • Servant quarters
  • Bathroom
  • Well/Cistern
  • Dovecote
  • Stables
  • Kennels
  • Courtyard
  • Gardens

Political function

  • Hall of Justice
  • Dungeon/Prison/Oubliette/Tower
  • Throne Room
  • Vault/Treasury

Noble quarters

  • Drawing Room
  • Bower
  • Rooms for the Lord/Lady
  • Formal sitting room
  • Informal sitting room
  • Private study
  • Personal library
  • Private dining room

Research

  • Library
  • Alchemy lab
  • Solarium
  • Wizards quarters

Religious

  • Temple/Church
  • Clergy quarters

Can you think of some more?

Editing to add the suggestions from the comments.