Can users on the top floor set up a canopy on the roof?

You need to go through planning and other procedures for approval and construction, otherwise it is illegal.

According to the Property Law, the scope of part * * *: the basic structural parts of the house, such as columns, roofs, external walls and basements; Public parts and accessories of the house, such as stairs, fire fighting equipment, corridors, water towers, water pipes, gas pipes, etc.

Therefore, the roof belongs to the public area and cannot be built privately.