In the master-bath I have an over-sized tub and separate glass shower stall that are right next to each other, both on-top of sub-flooring / a crawl space. (Crawl space is because house is built into the side of a hill, not flat ground).
The insulation in the crawl space under the shower and bath was a little wet when I pulled it off. Additionally, I've had termite damage to the plywood underneath the shower stall and basically no where else, indicating their attraction to moisture.
When I run both the bathtub and the shower -- turn on both hot and cold faucets on each -- and go back underneath the crawl space, I see no leakage, even with it running for a while. The pipes are dry, with no water dripping or build up, etc.
What do I do?