I have very noisy neighbours upstairs banging. I live in a flat. They do have children and that is fine but i dont think there is any soundproofing. I have cracks in my ceiling and things have fallen off walls. At certain points when they are running around upstairs the whole room shakes.
If the flats were built or converted to the standard of the day it can be a tricky issue to deal with (especially if the behaviour of the family is considered normal and, in that sense, not unreasonable). If they were not and the build is substandard this can be rectified – usually through the owners (or freeholder). The mechanisms for improvement depend upon ownership. You could ask the environmental health noise team to visit and investigate. If necessary you could request the private sector housing team also to assess the hazard rating under housing legislation. If you have not spoken to the occupants upstairs you might wish to discuss with them first – if they own their property and suffer the same issue they have a financial interest in improving the sound insulation.