|Great View From Avila Beach roof deck|
|Rotted subfloor, metal lath visible in closeup view|
|WTF? No, you don’t run irrigation lines under tile decks!|
|Heaved up tile in center of deck|
Here’s another shining example of a tile deck over a waterproofing system done badly, this time on a 3 million dollar home in Avila Beach.
There’s 1500+ square feet on the main level deck and roof deck. The decks were waterproofed with a metal lath, concrete and urethane with sand broadcast into it (sand gives thinset something to grab when installing the tiles). The manufacturer is unknown but several make a tile waterproofing system similar to the system here.
So what’s wrong you ask? It would be easier to answer with what’s right…NOTHING!
The tile & grout have cracks all over, indicating excessive movement in the sub-structure. The tile is heaved in several places, indicating moisture underneath. The tile is higher than the door thresholds, trapping water in the thresholds, allowing water out under the tile vis a vis the weep holes doors have built in them…
The deck/tile has no allowances for expansion/contraction that occurs in exterior conditions. No mortar bed to provide a firm base. The substrate it’s built over is only 3/4″ plywood, not the minimum 1″ as recommended by TCNA. The joists are woefully undersized, at 16″ on center and only 2″ x 8″, can’t possibly provide the necessary stiffness a tile deck requires.
This deck is a total tear off and redo, sans tile. The deck is obviously not designed for tile, but some idiot went ahead anyway…
Estimated costs to repair and redo with a traffic coating-$70,000-$80,000…
and tile is not an option!
Central Coast Waterproofing, the deck experts, is a authorized installer of Mer-Kote tile deck waterproofing systems. For your next tile deck project, call the experts at 805-545-8300 or pay the price of failure!