We are building a pool here on the outskirts of Managua, Nicaragua. The sprayed on concrete process is not available here, so we are doing it the old fashioned way; Pouring the floor first and then forming up the walls and pouring that. I will have a cold joint where the vertical walls meet the slab. I've been looking at a product made from PVC, made in the states, and is 6" wide. This ribbon of PVC is inserted half way into the fresh concrete of the slab, leaving 3" sticking into the air. The concrete for the walls is poured over it, leaving this PVC ribbon imbedded in the middle of the cold joint seam. You builders out there - is this necessary or is this overkill for this application? A 100' roll of this stuff is nearly 100 lbs. and to get it down here in some ones luggage won't work as it will exceed the weight limit. Should I go with the cold joint, seal it up the best I can with some sort of epoxy sealant painted on 24" above the joint and 24" away from the joint on the floor? We'll be putting on a pile of concrete all around the bottom corners of the pool, where the wall meets the floor. Maybe that is enough....?