Schluter Systems KERDI-FLEX Lightweight, Polyethylene, Vapor Retardant, Waterproofing Membrane Joint Sealing Strip Roll, 12 mil Thickness

Product Features:

• Flexible Movement Joint Protection: Pliable polyethylene strip seals expansion and construction joints where large movement is expected in tiled wet areas.
• 12 Mil Waterproofing Strip: Durable 12 mil polyethylene construction supports dependable waterproofing across critical joints, transitions, and tile assemblies.
• Designed for Schluter Systems: Works with DITRA, KERDI, and KERDI-DS membranes to maintain waterproofing continuity throughout bath and shower installations.
• Anchoring Fleece on Both Sides: Dual-sided fleece bonds securely with thin-set mortar, helping achieve full coverage and a reliable waterproof connection.
• Customizable Sheet Design: Flexible strip can be molded, shaped, and cut for complex showers, detailed transitions, corners, and specialty tile layouts.
• Expansion Joint Compatibility: Ideal for covering existing expansion, structural, construction, and flexible edge joints in tile waterproofing applications.
• Enhanced Movement Capacity: The center section can be tucked into the joint cavity before bonding to provide flexibility where added movement is expected.
• Secure Thin-Set Installation: Compatible with Schluter-SET, ALL-SET, FAST-SET, or unmodified thin-set mortar for strong, consistent tile membrane bonding.
• Waterproof Floor-to-Wall Transitions: Maintains waterproof integrity when overlapped at least 2 inches onto uncoupling membranes at seams and wall junctions.
• Ready for Tile Installation: Once seams, corners, joints, and connections are fully bonded and waterproofed, the finished tile covering can be installed.

Product Description:

Schluter-KERDI-FLEX is a pliable waterproofing membrane strip designed to waterproof movement joints in bath and shower installations. Its sheet form allows it to be molded and cut to any imaginable shape, making waterproofing of even the most elaborately shaped shower a simple task. It is covered in an anchoring fleece on both sides, allowing it to be set in place with thin-set mortar, and has the flexibility needed to accommodate large movements over time. Product Features Vapor Retardant The Schluter-KERDI waterproofing membrane has a very low water vapor permeance, making it an excellent waterproofing membrane for shower, bath, and steam room installations. Flexibility to Accommodate Movement Over Time Schluter-KERDI-FLEX is specially designed for waterproofing movement joints, as it can stretch and form to accommodate movement over time.

At 12 mil thick, KERDI-FLEX is manufactured from flexible polyethylene for specialty waterproofing applications over Schluter-DITRA at existing expansion and construction joints. It is used with DITRA, KERDI, and KERDI-DS membranes to continue the waterproofing layer across critical floor joints, floor-to-wall transitions, and other areas where dependable waterproof membrane for tile and flooring underlayment protection are required. Available in 5-inch and 10-inch widths with 16' 5" and 98' 5" length options, KERDI-FLEX provides versatile coverage choices for detailed joint treatment, extended waterproofing runs, floor underlayment assemblies, and professional tile installation projects. The multiple roll configurations also allow installers to select an appropriate amount of flexible waterproofing material for residential or commercial bathroom, shower, flooring, and home improvement applications.

When installed with KERDI or KERDI-DS, the membrane must remain separated at existing expansion, structural, and flexible edge joints before KERDI-FLEX is bonded over the opening. Schluter-SET, Schluter-ALL-SET, Schluter-FAST-SET, or unmodified thin-set mortar may be used, and the center section can be tucked into the joint cavity to provide additional movement capacity while preserving shower waterproofing continuity. This detailing method supports a continuous waterproof barrier beneath finished bathroom tile and shower tile assemblies while allowing the underlying joint to perform as intended. KERDI-FLEX can be incorporated beneath ceramic tile, porcelain tile, stone tile, marble tile, granite tile, mosaic tile, glass tile, floor tile, and wall tile finishes where the surrounding Schluter waterproofing system and tile assembly are suitable for the application.

For installation with Schluter uncoupling membranes, fill the cut-back cavities with mortar in an area approximately 8 inches wide and centered over the joint. Comb additional mortar using a 1/4 inch x 3/16 inch V-notched trowel or the 1/8 inch x 1/8 inch Schluter-KERDI trowel, then apply a centered 5 inch wide strip and firmly press it into place to achieve full coverage while removing trapped air and excess mortar. The specified 5-inch strip can be formed with KERDI-FLEX or compatible KERDI-BAND, while wider KERDI-FLEX material can be cut and shaped as required for specialty waterproofing details. Proper mortar contact helps integrate the strip securely into tile membrane underlayment and uncoupling membrane installations while maintaining dependable coverage through critical construction joint areas.

At seams and floor-to-wall transitions, KERDI-FLEX must overlap the uncoupling membrane by at least 2 inches to maintain waterproof integrity. Where fixed building elements will not accept a thin-set mortar bond, connections may be completed with KERDI-FIX or a suitable trowel-applied waterproofing compound, including moisture-curing urethane sealant. After all seams, corners, and connections are fully bonded and waterproofed, the finished tile covering may be installed. Following the specified overlap and connection requirements helps maintain a continuous water barrier beneath bathroom tile, shower tile, floor tile, and wall tile installations while protecting moisture-sensitive areas around transitions and joints. With multiple width and roll length variations available, KERDI-FLEX offers adaptable waterproofing coverage for detailed shower waterproofing, bathroom waterproofing, flooring underlayment, tile installation, renovation, and new construction applications.