Strataflex Literature:     Product Data     Installation     Specifications     SDS     Warranty

Features and Benefits


• Double stick lap joint for easy application

• Protects against reflective cracking and


• Suitable for interior and exterior use

• Reduces live and dead load failures

• Safely covers asbestos flooring and provides

   an effective barrier against radon and mold

• Eliminates need to cut tile to meet

   control/cold joints

• No need to remove old floors or recess new


• Can be used for thin-bed and medium-bed


• Self-bonding, self-seaming and self-healing


• Tile can be installed the same day as


• Serves as a waterproof/vapor barrier

• Works with radiant-heated floors and tile

   warming systems

Strataflex Waterproofing Membrane

Strataflex is a high strength, self-bonding, elastomeric sheet applied membrane designed for use under interior or exterior floor surfaces that require waterproof protection.


How It Works

Strataflex is a 40 mil (approx. 1/16") thick, high strength self-bonding, elastomeric sheet membrane composed of a base layer of polymer modified elastomers permanently laminated to a unique “stress flex” fiber sheet with a 2" double stick lap joint. Strataflex is designed for use under floor surfaces, such as stone, ceramic and porcelain tile, wood and commercial grade vinyl tile that require protection from water penetration, structural and thermal movement and Moisture Vapor Transmission.


Strataflex utilizes 2" double stick lap joints to form a continuous, impervious water barrier that provides long lasting waterproof protection.  At perimeters or cut areas an NAC approved polyurethane sealant may be used and 6” Seam Tape may be used at floor to wall, wall to wall, wall to ceiling joints, at drains and protrusions. 


NAC TAC, NAC TAC II or NS97 Primers are necessary components of NAC sheet membrane systems.


Strataflex provides protection from in-plane, structural movement up to 3/8" for floors requiring crack isolation protection, 


For protection against Moisture Vapor Transmission (MVT), use Strataflex and the appropriate NAC primer to provide protection of 10#/1000SF/24HRS when used with NAC TAC or NS97 Primer or 7#/1000SF/24HRS when used 
with NAC TAC II Primer.



Use Strataflex membrane OVER:


Concrete: Poured, pre-stressed and pre-cast concrete, concrete backerboard, mud beds, gypsum, lightweight concrete and patching compounds. 


Wood: Exterior or exposure 1 plywood, APA-rated sheathing, Sturd-I-Floor, hardwood, tongue and groove and OSB with standard face. (Gap between sheeting as required.) 


Other Substrates: Ceramic and porcelain tile, stone, terrazzo, VCT/VAT, metal, painted and sealed floors and floors damaged by dry shrinkage and structural movement. 


Use Strataflex membrane UNDER:


Thin & medium-bed mortar installations (ANSI A118.4) of ceramic, porcelain, stone, marble, slate, granite tile, pavers, brick, and other finished floors are also acceptable; check with manufacturer.

Wood & VCT Installations
Due to the nature of the overlap joint on Strataflex membrane, the overlap joint may transfer through the finished VCT. We recommend using ECB membrane in these applications. If additional sealing is desired then apply SubSeal® Liquid Waterproofing Membrane over seams. When installing wood or VCT over membrane, a solvent free or urethane glue/adhesive must be used. Follow  general membrane installation instructions.


Ideal for use with radiant heated floors and low voltage tile warming systems.



Strataflex is available in 3'x50' rolls (150 sq. ft.)


Phone: 330-644-3117/800-633-4622   Fax: 330-644-3557    Email:

© 2020 National Applied Construction Products, Inc.