Abstract: A floor system includes a clamping ring drain assembly for funneling water to an opening of in-floor drain plumbing. The drain assembly includes clamping rings and a cover for the input opening. A waterproof membrane has marginal material defining a hole, with the marginal material being located outboard of the upper clamping ring. A customized floor drain flasher adapter membrane has an outer first ring bonded to the marginal material of the waterproof membrane, creating a double thick ring outboard of the clamping rings. The adapter membrane further includes a ring of transition material sloping to the clamping rings. The adapter membrane has a preformed shape selected to match a vertical dimension at the construction site, so that the adapter membrane is not bent, stretched, folded or wrinkled during construction/installation, hence preventing water leaks, puckering of the membrane, and membrane cracking.

Abstract: A method of constructing in-floor drains includes measuring a vertical distance from a component in the floor to an in-floor drain pipe, and ordering a customized floor drain flasher adapter membrane having an outer ring for engaging the floor component, such as a waterproof membrane, and having an inner ring for positioning adjacent an entrance to the drain pipe, the outer and inner rings being spaced apart a dimension correlated to the measured vertical distance. The method includes installing the customized floor drain flasher adapter membrane to connect to the in-floor drain in a way that reduces leaks and that prevents unnatural and uneven folding, bending or stretching of the membranes. Preferably, an inventory of different types of pre-manufactured floor drain flasher adapter membranes are pre-manufactured for just-in-time shipment. The adapter membrane can be attached to a pre-formed waterproof membrane, or to a liquid-formed membrane formed on the construction site.