I had posted in the comments of this post but figured I should make my own post. https://www.houzz.com/discussions/2371243/mystery-moisture-in-slab-ruined-engineered-wood-floor-now-what

Background info:

We have moisture damage in random locations of our living room and master bedroom floors. These rooms are at the back of the house. We've verified with two plumbers that there are no leaks in the pressurized lines or sewage pipes.

In the backyard we have a pool and concrete deck. We think it is improperly graded deck. We are separately resolving that issue but there are no guarantees from anyone that this will resolve the moisture issues, or if this is even the origin of the moisture.

About the house:

- We're located in a suburb of Houston. While we are not near the coast, we are about 1 mile from a river.

- The house was built in 1995 and has a concrete slab.

- We have tile and engineered hardwood on the 1st floor.

Timeline of events:

- The "trouble areas" had carpet when we moved in. We installed engineered hardwood floors in 2014 by a company that is now out of business.

- In 2017, after Hurricane Harvey, we had portions of moisture damaged hardwood flooring removed and replaced with the same type of flooring by a remediation company.

- Several months ago, we started noticing moisture issues on the floors again. They were probably present well before, but we just didn't notice them.

The dilemma (tile, wood, or carpet):

We were planning on replacing with tile, but a reputable flooring company told us that it is okay to use wood if installed correctly. He thinks it was just improper installation and that a moisture barrier was not used.

He has suggested doing a calcium chloride test, then using titebond 531 + epoxy floor moisture barrier.

Should we try wood floors again or should we put tile or carpet? After this is all done, we will have spent nearly $25K and I would be horrified if we have moisture issues on the flooring again. Something tells me it is a dumb idea to try wood floors again but the flooring guy is confident he can do this. My only issue with tile is that we would have mismatched tile on the 1st floor (the other tile we have is no longer manufactured). Would carpet with no moisture barrier let the slab "breathe" better?

I appreciate any help. Thanks!