We use Schluter

Schluter Shower System
Contrary to popular belief, tiles and grout joints are not inherently waterproof,
and must be installed in conjunction with a waterproofing system that effectively manages moisture and prevents mold growth.
The Schluter Shower System is an integrated family of products that together form a fully bonded, watertight assembly for tiled showers. &nbsp The Schluter Shower System eliminates the risk of failures due to water and vapor penetration. From drains to shower benches to waterproofing pipe seals, Schluter Systems offers everything to ensure a dependable and watertight installation.

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