Schluter Systems Kerdi Membrane Is The Best Solution For Waterproof And Watertight Tiled Shower Or Steam Room .Schluter Systems Kerdi Waterproof Membrane Is A Bonded Membrane & Vapor Retarder Made Of Soft Polyethylene ( have Crack Prevention capabilities ) , Both Sides Of Schluter Systems Kerdi Waterproofing Membrane Have Special Webbing Synthetic Fibers That Allows Perfect Bond With Thin-set Mortar . Tiles Can Be Installed Directly On Top of Kerdi Membrane . We Recommend To Use Schluter Kerdi Trowel In Order To Apply Mortar Evenly On The Surface . Schluter Systems Kerdi Waterproof Membrane – Choose your Custom Size and we will cut it for you. Its 3.3 Ft Wide , Length would be customized depending on your SqFt , Membrane Thickness 8 Mil .