I have never laid tile on an outside covered porch and am wondering about a moisture problem under the tile, especially on the outside edge. Deck is 3/4 exterior ply, well supported and covered, however, water will reach back 2-3 feet in wind.
I am thinking wonder board, sealed seams with glass tape, thin set, then tile on the horizontal. But what about the edge? Same treatment? Or use Red Guard to seal plywood edge first, then wonder board, etc.
The house is in Santa Rosa, CA.
if it were me I would treat all the ply or put a membrain down first then go with the rest and seal all the tile with a ggod sealer but I tend to do things that according to my wife will last forever and with stand a hurricain