Second story tile porch floor reflashing

My 12-year-old second-story covered porch with a tile floor needs some attention. Several layers of galvanized flashing on the outer edge have rotted out. There doesn’t seem to be any water leaking through the floor into the outdoor living space below, but discoloration issues on the cedar facia. This is South Texas, so I do not deal with freezing often, and not tons of rain.

As a new user, I cannot post a picture. But the installation appears to be rubber membrane over a plywood subfloor, with a 3/4 inch layer of sand?, And then mortar and tile. The builder inserted galvanized flashing between the rubber membrane and the sand, possibly with some kind of adhesive.

The question is, what can I do without pulling up the tile floor which is still reasonably solid? I really just want to transition from the rubber membrane to new flashing with a drip edge. does anyone have a suggestion for me? Thanks!

Post some pics. Interior drains? Guttered? Any of the mortar in the tile is cracked? I got into one of these a few years ago, but we get below freezing every winter.

I think since you have introduced yourself,
You can post one pic at least.
With further discussion, you will be able to post more pics pretty much immediately.

Trying to post a picture, it says I cannot. Sorry!

Yes, the mortar is leaking. I’ve sealed it and the tile several times, but movement from hot/cold seems to open it up quickly.

After a good rain event the drip edge will drip for 2-3 days as the water finds its way out. But the rubber membrane seems to be intact, nothing through the ceiling at all. My concern is how to transition that membrane, which ends horizontally at the edge of the floor, to the flashing.

Maybe easier if I throw out my ideas?

  1. Take last course of tile off the floor. Remove sand/cement layer. Add more rubber membrane, with good sealing technique between the two layers?, so the rubber now makes the corner from horizontal to vertical and can layered over galvanized flashing and drip edge. (This idea is not my preference, as I’m trying to avoid taking up the floor.)


  1. Put on two layers of flashing. One immediately under the tile edge to address water running off the tile, and another one under the rubber membrane to address water that is seeping down through the mortar and sand to run out on the rubber membrane.

If I could keep things from rotting out and get 5-6 years out of the fix, I’d be pretty happy. I think eventually the whole floor will have to come up.

Wrong. Your concern is the water infiltration into the tile. Once there is moisture in that floor, you’ve lost stability, and it will continue to degrade. The EPDM will hold up, the tile won’t. The freeze expansion is 10%, water to vapor at 212F is 1700X

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Replace the metal with stainless steel. Rebuild everything from scratch. Use peal and stick base 2 layers thick offset 50 percent. Then use CIM 1000 to glue down 1/4 inch concrete board. Use 4 inch by 4 inch stainless-steel perimeter flashing with the back and over laps set in The CIM. Use stainless counter flashing. Put porcelain tile over the concrete board with modified flexbond for porcelain. Use laticrete grout.