How to Install a Linear Shower Drain

Liner drains transform a standard walk-in shower into a high-end, curbless wet room. Unlike a traditional circular drain that requires the floor to slope in four directions, a linear drain allows for a simple, single-plane slope toward one side, creating a cleaner aesthetic and allowing for larger-format floor tiles. Success here relies entirely on your subfloor preparation and the integrity of your waterproofing. If your drain isn't perfectly level and properly integrated with your shower pan's waterproof barrier, you are inviting subfloor rot and leaks. Take your time during the framing phase to ensure your drain placement allows for a consistent slope of at least 1/4 inch per foot.

  1. Position the drain outlet first. Position the drain body near the wall where the shower entry will be. Ensure the drain flange sits flush with the subfloor and the outlet aligns perfectly with your existing plumbing trap.
  2. Level the drain perfectly. Fasten the drain body to the subfloor using the manufacturer's specified screws through the mounting tabs. Use a level to ensure the drain is perfectly horizontal across its entire length.
  3. Test the trap connection now. Connect the drain outlet to your P-trap using PVC or ABS solvent weld as required by local code. Perform a water test by filling the drain with water to verify there are no leaks at the trap connection.
  4. Slope the floor toward drainage. Pour or install your pre-sloped shower pan material so that it sits flush against the drain flange. The floor must slope away from the room and directly into the drain channel without any low spots.
  5. Seal the leak pathway. Apply a waterproof bonding flange or liquid membrane over the drain flange and onto the surrounding floor area. Ensure the membrane overlaps the drain's integrated weep holes or flange edge according to the specific manufacturer's instructions.
  6. Flush the tile to drain edge. Lay your tile up to the edge of the drain channel, leaving a small gap for the grate. Ensure the tile height is exactly flush with the top of the drain collar for a clean finish.