Does the airspace belong to everyone?

Since a week, we are out of internet at the office in Sliema. As we are using the  wireless internet provided by Vanilla, we climbed on our roof to check the connection of our antenna just to realize that as a new building has been finished in Tower Road/Bisazza street, we have lost our connection to the emitting antenna. I wonder if there is some sort of regulation, it is not correct that with the erection of buildings, one looses the wireless services one used to enjoy in the past…