Is there anything special to look out for when inspecting a negative edge pool?
Thats a really good article, especially as these become more en-vogue. I especially liked the take on waterproofing the shotcrete/concrete before tiling. Too bad there really isn’t a way to tell that on an inspection, and willing to bet more often than not, it’s not done.
Your correct, very few pool contractors think to waterproof before tiling. However if the tile is laid properly (in a full bed of thin-set or tile mortar) it wont really cause any problems. If you see calcium build up that looks like it’s coming from between the tile, it was most likely laid by applying “pats” of thin-set to each tile. Not the way to go. This goes for all concrete pools not just negative or vanishing edge pools.
On vanishing edge pools the edge needs to be extremely straight and level, there is very little tolerance. Weather the spill wall edge is angled and in which direction depends on the effect that’s desired. Also an auto fill/level and check valves are very important. You don’t want the main pool draining back to the catch basin when every thing is turned off and evaporation is pretty extreme because of all the water exposed to the air going over the edge.
Other considerations are the size of the lift pump and related plumbing. A lot of water needs to be moved but it should be done with out causing any surface turbulence. They also tend to have more complicated control systems too. Beyond that it’s a pool and every thing you look for in any other pool needs to be addressed too.
BTW: the guys at “Genisis 3” were some of the first to do these and are also some of the best around.