I live in a flat & the flat above me occassionally has a loud banging sound coming from their water pipes when they run their hot water. It sounds like trapped air but not sure. They are not too concerned by it. However, as I live below them I am concerned that a pipe may burst causing extensive damage. Is that likely? Would a residential water pipe burst? What could be the cause of the noise & how can it be rectified? Thanks
What you describe is water hammer, usually caused a ball valve shutting down when there is too high a pressure in the cold water cold water system. This is not cured by turning down the stop valve on the cold water main, this only reduces the flow of water - not the pressure. If this is the case you will need to fit a surge arrester. Call a good plumber.