The following room require a mezuzah with a berachah:
- Entrance into a house
- dining room
- living room / den / family room
- office / study
- attached garage. This includes the large sliding garage door.
The following require a mezuzah without a berachah:
- storage room
- walk-in closet (36 sq. ft. or more)
- doorway to staircase or hallway
- office used exclusively for business
- Bais Midrash
- a room that is in between 36 sq. ft. and 64 sq. ft.
- a room with out a door.
- a room with a door post on the right side even if there is no doorpost on the left side.
- detached garage
Rooms that do not require a mezuzah:
- doors that are used for exit only, like emergency exits or fire escapes
- room without a roof
- doorway less than 36″ high
- garbage room
- door sealed shut
This list was based in part on the list found in ‘The World of Tefillin & Mezuzos’ by Rabbi Zeev Rothschild
If one is renting a motel room by the month they should put a mezuzah up. This was told to me by Reb Avraham Tzvi Wosner, Posek for the Vaad Mishmeres STaM.