Installing almost any type of tile is the same whether it's designed for the interior or exterior. How the floor is prepared for the installation, however, is another matter.
Porcelain tile outside over wooden deck porch I have just installed porcelin tiles over existing wooden porch deck using lightweight concrete board and used flexibond motar cement for exterior use and I am now being told that it probably will not hold up through the winter.
Satisfactory exterior installations must be able to drain water from the system before it gets a chance to absorb into either the tile or the layers below the tile. Since most tiles are water impermeable, the only water that can get into the system goes through the grout joints or through the substrate itself.
Plywood and concrete are conventional substrates, but I've seen too many problems—caused by moisture getting trapped underneath the tile—on exterior tile installations using them. A few years ago, looking for a better alternative that would also allow water to drain through the assembly, I began installing deck tiles over McNichols square-mesh molded fiberglass grating panels instead.
Cement board manufacturers pretty much all restrict their materials from being installed directly to any plank material. So yes, a layer of plywood is appropriate over the existing deck boards and under the cement board. There are tile-on membranes that can go right over the plywood.
Laying tile over a plywood subfloor can be a bit tricky, but if you take the time to .... in PVC Decking PLUS a Lightweight Paver for Resurfacing Decks and Patios. How to Insulate and Level a Garage Floor Ron Hazelton Online ...
Use a Patented Technique to Guarantee Success . Laying tile over a plywood subfloor can be a bit tricky, but if you take the time to prepare the sub floor properly, you can enjoy a new tile floor that will last for a lifetime.
Finally - installing the outdoor tile over the wood deck If your deck is good to go, then now's the time to start exploring the wonderful world of deck tiles. Greatmats offers the best tiles for outdoor deck tiles systems to fulfill any and all designs while meeting quality standards.
It is a good idea to put half inch plywood underlay to strengthen the floor before using modified thin set to put the tile directly on wood. If the subfloor is 5/8 or 3/4 you can probably apply tile directly to it with no problem.