We hear loud bangs in two walls in one room of the house. It's loud enough that it makes you jump. My husband has checked under the house for cracks or moving or cracked wood, there are no cracks on the brick fireplace or mirrors on the wall. It sounds like someone is hitting the wall with a baseball bat. What could it be. Earlier tonight it was on the wall with the glass French doors. The house is only 20 years old and this has been going on for a couple of years. We could really use your help. Thank you Jill ...... **** moderators note... email edited out

This has nothing to do with water, there are no pipes in these 2 walls. When it happens on the French Door wall it sounds like a large bird flew into the glass. It's loud. It makes us jump.

Where are you located? How long have you owned the house? Are other houses around you built by the same builder? Do you have a poured concrete foundation? What are the floors made of? Is the fireplace on an inside or outside wall? Does it have a typical full brick chimney, or flue?

(Wood can make really loud noises when contracting or expanding, without always being evident. Concrete foundations can sink without cracks. My parent's house had an attached carport with the center post on a 4' concrete pier that sank 10 inches, making the whole roof bulge upwards in the middle, and it wasn't all that evident without peering at all the lines of sight.)

Are there any air ducts in those walls?