I live in a new-construction house that my dad had commissioned, completed around 2006. I do not think the showers were tiled properly. We've had two showers leak through to the floor below. The first shower which is a bathtub/shower head combo leaked through a gap between the external tile ledge and the actual tub insert. The second shower, which is a standalone, leaked through tiles which weren't grouted properly under the in-shower seat. We decided to re grout and seal all three baths just in case. Our third shower hasn't showed visible signs of leaking yet, but whenever we walk on the second floor near the shower after it hasn't been visited for a while, cracking sounds similar to what typical settling noises sound like come from inside the walls around the shower. I would suspect that since the shower is right up against the very edge of the house, it could be leaking on the edge down through the studs and we're not seeing it come through the floor. The house is built with Wood I Beams, and I'm mainly concerned that we could be doing structural damage to either the studs or the I beams. No one else in my household is concerned about it. My question is, how do I check to see if the shower is actually leaking, whether a slow or fast, and how do I fix it since our grout seems to just crack and get moldy after a year?

I have looked online and it seems that they have anchors, but the ones that I have don't? I really have no idea how to go about and fix it and would like to learn. [ATTACH]29764[/ATTACH] [ATTACH]29767[/ATTACH]