For the past two years we have been working on an addition to our log home (additions to log homes have their own special problems). We now have your photo hung in the work-in-progress addition for inspiration. The question we have at this point has to do with the shower tiles. 30 years ago we used marine plywood as a backing for our existing shower walls and put tile over this using canned tile adhesive. We have added a new bathroom in the addition and have again used marine plywood as a backing for the shower wall above the bath tub. Can we, or should we, use a latex based "thinset" to adhere the wall tiles to the marine plywood. The tile places we have checked on have no experience using marine plywood as a tub surround, but suggested using the latex based thinset to adhere the tile to the plywood. Everything is in place and there is no clearance for adding cement board or similar mat! erial to the marine plywood. What do you suggest we use?