The Gruen 90° Inside Corners are preformed, seamless waterproofing solutions designed to provide a watertight seal at critical junctions in tile installations. Made from durable, waterproof fabric, these inside corner seals reinforce membrane protection in showers, bathrooms, and wet areas, preventing water leaks, moisture buildup, and mold growth. The 4-mil thick construction ensures reliable waterproofing performance, making them ideal for residential and commercial tile installations.

Each package includes two inside corners, pre-molded for quick and effortless installation, eliminating the need for custom cutting or shaping. The flexible design seamlessly integrates with most waterproofing membranes, thin-set mortars, and tile backer boards, ensuring full coverage in hard-to-seal areas. Whether you’re a professional tile contractor or a DIY enthusiast, the Gruen 90° Inside Corners provide a hassle-free waterproofing solution that enhances long-term durability and protection in tiled wet spaces.