Pipe noises range from loud hammering sounds to high-pitched squeaks. The causes may be loose pipes, water logged air chambers, or water pressure that's too high. Anchoring exposed pipes is a simple solution; other remedies such as anchoring pipes concealed inside walls, floors or ceilings, may call for a professional.
Pipes are usually anchored with pipe straps every 6 to 8 feet for horizontal runs, 8 to 10 feet for vertical.
Banging - When you anchor a pipe, especially a plastic one, leave room for expansion.
Don't use galvanized straps on copper pipes.Banging - When you anchor a pipe, especially a plastic one, leave room for expansion.
Solution: Cushion it as you would a banging pipe.
Check for Loose pipes