and
will stop and start between the decks expansion joints.BROKEN TILE LINES
One frustrating leak that can be elusive is a cracked tile line. Sometimes
the cracks are long and thin or hidden by coarse pool finishes. The cracks are
usually near the bottom of the tile
and
will stop and start between the decks expansion joints.
Notice the crack is not exactly at the bottom of the tile. but the depth of the crack is the thickness of the deck. The deck is a big concrete slab that broke away from the pool wall. This can be a serious structural problem. Lets take a look:
The crack is sometimes visible at the bottom of the tile, but in some areas, it can be tough to see. The dye is not too effective because the cracks are too thin and long.
This crack is resulting more from a deck settling problem, rather than a tile replacement problem. The deck is settling from poor soil compaction. and the tile line is at the fracture point, but notice the deck can also break from the pool wall on the top of the deck- which is good because the stress is relieved away from the pool wall. This crack can jump up and down between expansion joints on the deck. Just replacing the tile will just postpone the problem again.
An ideal, but expensive solution would be cut a deep expansion joint around the pool, so the deck will separate from the pool wall in the right place. Pinning the deck to the pool with iron rebar and hydraulic cement is also a good idea.
This repair is a major deal, and you need to seriously think about cutting the deck, The saw cut needs to be deep (4") which also means the saw cutter may have difficulty with making turns in oval pools. Drilling and anchoring the rebar rods can be hit and miss. Then you have to retile the pool and refinish the deck. For now, we have a temporary solution
This spa suffers from the same problem of a deck that is settling, forcing a crack underneath the tile line. The crack will separate the tile between the joints.
To repair this a clear silicon glue is applied to the joints of the tile. But first the water must be drained about 6" below the waterline and the crack must dry out for 3 days.
A temporary fix that lasts 3 years is a clear silicon glue that remains flexible as the deck settles. it sticks to tile line well, but the tile line and pool surface must be scrubbed clean with a wire brush and bone dry.