The KERDI-DRAIN flange kit connects Schluter's point drain system to a 3" PVC drain pipe below the shower floor. This is the critical waterproofing component — the bonding flange seals to the KERDI membrane with thin-set mortar, creating a continuous waterproof barrier from the shower floor membrane down into the drain pipe.

The 3" PVC version is for standard residential rough-in where the plumber has stubbed up a 3" PVC pipe. If your rough-in is 2" PVC, you need the 2" version instead. If it's ABS pipe, get the ABS flange kit.

How it works

The flange kit consists of the drain body (which connects to the pipe below), the bonding flange (which KERDI membrane seals to), and the adjustable height collar that brings the drain up to your finished tile level. The KERDI membrane overlaps the bonding flange and gets sealed with thin-set — this is where the waterproofing happens.

Installation overview

• Connect drain body to the PVC rough-in pipe below the subfloor
• Set the bonding flange at the correct height for your tile assembly thickness
• Apply thin-set to the bonding flange
• Overlap KERDI membrane onto the flange — minimum 2" overlap, fully embedded in mortar
• The strainer grate snaps into the top after tiling is complete

Specs

• Outlet: 3" PVC
• Bonding flange: Integrated — seals to KERDI membrane with thin-set
• Height: Adjustable to accommodate different tile assembly thicknesses
• Grate: Sold separately or included depending on kit version

Choosing the right drain

• PVC vs. ABS: Match your rough-in pipe material. PVC (white) is most common. ABS (black) is used in some regions.
• 2" vs. 3": Match your pipe diameter. Most residential is 2", but some codes require 3".
• Stainless steel: For exposed/decorative installations or commercial applications.

Pairs with

• KERDI waterproofing membrane
• KERDI-DRAIN strainer grate
• KERDI-BAND — for additional sealing at the membrane-to-flange overlap
• Schluter SET or ALL-SET mortar