I’ve recently purchased a brand new home and noticed that quite of bit of noise coming from the
walls. I knew some of it had to do with gas (heat) expansion and contraction. However, one thing that
puzzles and annoys me is the loud whack or sound of an object falling a great distance. It’s coming from
the 1st floor near the fireplace and it occurs whenever the bathroom sink, located above on the 2nd floor,
is turned on. I expected potential rustling or ticking noise but not that loud whack. It’s not continuous
either. Can you think of a plausible explanation for that loud noise? As I am under warrantee, I’d like to
address any potential problem, but I don’t want to put them to any unnecessary trouble if it’s part of its
natural phenomenon. Thank you!