When logged in to MyTimetable it is possible to navigate from the standard timetable view to the room view. You can find this view by clicking 'Room view' in the upper right hand of your screen:
Subsequently, you can add the timetables of rooms by clicking on 'Add timetable' and choosing 'Room' or 'Building':
When choosing 'Building', you are able to add all rooms belonging to a building. When choosing 'Room', you can add individual rooms. With buildings, for example, your screen would look something like this:
When you've added rooms according to your preferences, you are able to view the availability of these rooms. The ideal tab for this purpose is the one called 'Availability'. Use the calendar in the lower right hand of the screen to choose a date.