Schluter® KERDI-DRAIN FLANGE KIT 3" STN STEEL

The 3" stainless steel KERDI-DRAIN bonding flange — for installations requiring a larger drain connection and the flexibility of a no-hub mechanical coupling. This is the commercial-grade, renovation-friendly option: no solvent cement, connects to either PVC or ABS pipe, and stainless steel construction that won't corrode in a wet assembly.

Where the 2" drain handles typical residential bathroom flow, the 3" outlet moves more water faster — relevant in larger format showers, steam rooms, wet rooms, and commercial applications. The no-hub connection means you cut the pipe to height, clamp it, and you're done. No primer, no cement, no waiting for the bond to cure.

What's in the box

• KERDI-DRAIN flange body — 3" stainless steel with no-hub outlet
• Height adjustment collar
• No-hub coupling hardware for connecting to 3" pipe
• Assembly hardware

Key specs

• Body material: Stainless steel
• Outlet: 3" no-hub (mechanical coupling — connects to PVC or ABS pipe)
• Bonding: KERDI-FIX adhesive used to bond KERDI membrane to stainless flange (not fleece-bonded like plastic versions)
• Compatible grates: 4" Classic, Contour, Trendline, Tileable KERDI-DRAIN grate assemblies
• Compatible with: KERDI, DITRA, DITRA-XL waterproofing systems
• 10-year limited warranty

Important: stainless flanges use KERDI-FIX, not fleece bonding

The plastic KERDI-DRAIN flanges have a fleece-covered bonding surface that embeds in thin-set mortar. Stainless steel flanges do NOT have fleece — instead, you use Schluter KERDI-FIX adhesive/sealant to bond the KERDI membrane to the stainless flange. Make sure you have KERDI-FIX on hand before you start the membrane installation.

3" vs. 2" drain selection

• 2" drain: Standard for residential bathrooms. Handles typical shower flow rates without issue. Most common choice.
• 3" drain (this product): For larger showers (72"+), steam rooms, wet rooms, commercial installations, or anywhere you want faster water evacuation. Also specified when local code requires it.

Pro tips

• The no-hub coupling is reusable if you need to adjust — unlike solvent cement, you can loosen the clamp, reposition, and re-tighten.
• Stainless flanges should be bonded to the KERDI membrane using KERDI-FIX — apply a continuous bead around the full flange perimeter, press the membrane into it, and let it cure before tiling.
• Set your drain height before the KERDI-SHOWER tray or mortar bed goes in — you won't be able to adjust the pipe height later.
• The 3" outlet requires 3" rough-in pipe — confirm this during your plumbing rough-in, not after.

Pairs with: KERDI-DRAIN 4" grate assemblies (Classic, Trendline, Tileable), KERDI-FIX adhesive for membrane bonding, KERDI or DITRA waterproofing membranes.