In reply to message posted by WMullen: After the second floor toilet is flushed there is a LOUD noise, sounds like the pipes will come out of the wall. It only happens when this toilet is flushed. Any ideas?
Does the noise last only while the waste flows through the waste pipe, or does it occur for some time after (during the time the tank is refilling)? In the first case, you’ve got noise generated by a poorly insulated drain (cast iron is quiter than plastic). In the second, you could have water hammer from a bad tank fill valve or poorly anchored supply pipes.