A waterproof membrane, Schluter -KERDI System, was set over the cement backerboard using thin-set mortar.
Schluter-KERDI is made of soft polyethylene covered on both sides with a special fleece webbing to anchor the membrane in the thin-set mortar.
Tile is now ready to be set after this 'wet wall' passes city inspection. Holiday weekend so inspection cannot be done for 4 days...