Construction techniques
Vanishing edge returns were plumbed into the floor to eliminate turbulence and maintain the glassy surface that makes this feature popular. The manifold, which is fed at each end, is a complete loop to ensure a balanced flow at the various returns. Sumps are utilized to maintain the proper dimensions beneath the drain covers (this was long before the VGBA existed).
After installation, the pipes are covered to keep them below and out of the concrete. Since the vanishing edge basin was designed to cantilever over the slope below, the spa’s plumbing was routed under the catch basin and covered to keep it out of the concrete structure.
Dimensional lumber and plywood was utilized to build sturdy forms. The forms were assembled with screws so that the lumber could be reused on subsequent jobs. Prior to the placement of the steel, the forms were coated with a form release to aid in their removal.
The shotcrete surfaces were later cleaned to remove any form release oil that could interfere with the adherence of waterproofing or finish layers.