Every showerhead pipe, body spray, and hand shower requires a penetration through your waterproofing layer. Without a proper seal at that penetration, you've just put a deliberate hole in your waterproofing system. KERDI-SEAL-PS is Schluter's prefabricated waterproofing seal specifically designed to handle that transition cleanly and reliably.

The seal has an over-molded rubber gasket that fits snugly around the supply pipe and a fleece-covered bonding flange that embeds into thin-set mortar — same fleece anchoring system as the KERDI membrane itself. The result is a continuous waterproof connection from the membrane, around the pipe, with no gaps and no field improvisation required.

Why not just use caulk?

Caulk around a shower supply pipe eventually fails — thermal cycling, movement, and soap buildup break it down over time. KERDI-SEAL-PS creates a mechanical bond between the waterproofing system and the pipe, not an adhesive joint. It's warrantied as part of the Schluter Shower System. Caulk is not.

Installation

Apply thin-set to the wall substrate, press the KERDI-SEAL-PS fleece into the mortar, then overlap the KERDI wall membrane onto the bonding flange with a minimum 2" overlap on all sides. The rubber gasket seals against the pipe; the fleece-to-mortar bond integrates the seal into the waterproofing assembly.

Key specs

• Designed for supply pipe penetrations (showerhead, body sprays, hand shower)
• Over-molded rubber gasket for pipe seal
• Fleece-covered bonding flange for mortar anchoring
• Compatible with KERDI, DITRA, and DITRA-XL membranes
• Available in sizes to match standard 1/2" IPS (iron pipe size) supply stubs
• 10-year limited warranty (as part of Schluter Shower System)

Pro Tip

Install KERDI-SEAL-PS before the membrane goes on the wall — work from the drain up, not the other way around. Seal the pipe penetration first, verify the rubber gasket seats fully against the pipe, then lap the membrane over the bonding flange. Trying to retrofit the seal after the membrane is up is messy and usually results in a less reliable joint.

Pairs with

• KERDI waterproofing membrane (wall application)
• KERDI-BOARD building panels
• KERDI-SEAL-MV mixing valve seal (for the valve body — sold separately)
• KERDI-FIX (for additional sealing around unusual pipe configurations)