KERDI Shower Pan Mistakes and How You Can AVOID Them

Tutorial: How to Avoid Common Mistakes When Installing a KERDI Shower Pan

Step 1: Evaluate and Prepare the Framing

• Check the subfloor panels for any signs of damage like mold or warping. Remove and replace damaged panels using a circular saw and pry bar.
• Inspect the floor joists to ensure they are spaced appropriately (16 inches on center), free of excessive holes or notches, and level.
• If the floor joists are not level, reinforce them by sistering new floor joists using 2x6s or 2x8s and secure them with 3-inch construction screws staggered every 8 inches.

Step 2: Properly Install the Subfloor

• Use 23/32 or 3/4 inch plywood subfloor panels to prevent deflection that can lead to leaks.
• Apply a 1/2 inch bead of construction adhesive to the floor joists and secure the plywood panels with 2-inch construction screws following a specific screw schedule to prevent deflection.
• Ensure the subfloor is level in every direction to facilitate proper drainage for the shower pan.

Step 3: Customize the KERDI Shower Pan

• Cut the perimeter of the KERDI shower pan by 3/4 inch to ensure a flat surface for wall tile installation.
• Adjust the size of the shower pan accordingly by cutting off excess material from both sides.
• Reinstall the 3/4 inch perimeter to maintain a flat and level surface for tile installation, reducing the need for complex tile cuts.

Step 4: Extend the KERDI Pan (if needed)

• Extend Schluter Shower pans using dry pack mortar like Mapei 4-to-1 Mud Bed Mix.
• Mix the Mud Bed Mix before setting the KERDI shower pan and apply it over the wet thin-set mortar to extend the pan.
• Allow the Mud Bed Mix to fully cure to ensure waterproofing integrity.

Step 5: Properly Apply Thin-Set Mortar

• Use Schluter ALL-SET for setting KERDI shower pans and follow the manufacturer's instructions for mixing consistency.
• Apply the thin-set with the recommended trowel, ensuring the surface is hydrated to promote proper bonding.
• Apply the thin-set parallel to the shortest side of the shower pan to allow for air escape and create a solid supporting bed for the pan.

Step 6: Waterproof the KERDI Shower Pan

• Use Schluter ALL-SET or unmodified thin-set mortar to bond KERDI-BAND for waterproofing.
• Follow the mixing instructions for setting membranes to maintain the right consistency for bonding.
• Use the Schluter KERDI trowel for applying thin-set and embed the banding with a 6-inch drywall knife to ensure proper waterproofing.

Step 7: Use Prefab Corners for Waterproofing

• Utilize KERDI-KERECK inside and outside corners to waterproof the corners effectively.
• Apply thin-set to the pan and wall, add the KERDI-KERECK inside corners, and then apply the KERDI-BAND to ensure watertight performance.
• Use outside corners to waterproof the curb to the KERDI pan for a complete waterproofing system.

By following these steps meticulously, you can avoid common mistakes when installing a KERDI shower pan and ensure a successful, waterproof, and tile-ready shower installation.