Miracote MiraFlex Membrane B

Miracote MiraFlex Membrane B is a specially formulated polymer emulsion waterproofing designed for use over metal flashing, beneath ceramic tile, marble, quarry tile, below grade, between slab and under Miracote composition floors and decks.

MiraFlex Membrane B is recommended for tank lining in potable water drinking systems. MiraFlex Membrane B is based on a unique acrylic emulsion that dries to form a tough water and vapor resistant film. The latex is water based, environmentally friendly and does not contain any solvent. Cold weather application is achieved with this membrane technology.

Applied by roller, trowel, spray or squeegee, MiraFlex Membrane B offers tenacious adhesion, water protection, and is more resistant to impact than most membranes. It is applied to floors and molded up onto bases, over curbs, etc. without the use of any adhesive other than its own composition. Among the surfaces Membrane B can cover are lath, metal flashing, concrete, tile and other metals including copper. For wood surfaces, consult Crossfield Products Corp.

The final thickness of MiraFlex Membrane B is 25 mils dry (standard application, two applications of 23-25 mils wet) and 30 mils dry (polypropylene fabric reinforced). Laboratory tests have established that MiraFlex Membrane B will bridge concrete cracks up to 1/8″ (3.2mm) at temperatures as low as 0*F. However, prudent design would assume that the product could be expected to bridge a crack of up to 1/16″ (1.6mm) at its widest point.

Where to Use:

As a waterproof membrane directly under seamless composition floors (Miracote or other), ceramic tile, quarry tile, marble, etc. For application as mechanical equipment room waterproofing or computer access floor waterproofing for below grade or between slab applications, consult separate Crossfield Products Corp. specifications.

Technical Info
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  • Excellent adhesion to tin, aluminum, copper, steel, nickel, and galvanized metal.
  • Forms a monolithic, tightly adhering, molded membrane across floors and up bases, curbs, etc.
  • Environmentally safe, VOC compliant.
  • Reduces reflective cracking caused by substrate movement.
  • Thin section does not interfere with building elevations.
  • Unlike sheet goods, fluid applied Membrane B can easily be applied to irregular shapes.
  • Quick drying – Touch dry in 1-2 hours, fully dry in 12 hours.
  • Cures at cold temperature as low as 40°F (4.4°C).

Technical Info

  • Waterproofness No passage of water (Resistance to passage when subjected to 27.7″ head of water (hydrostatic pressure of 1 lb/ft) for one month.)
  • Elongation (with fabric) ASTM D2370 82%
  • Tensile Strength (with fabric) ASTM D2370 1586 psi
  • Bacteria & Fungus Resistance ASTM G22 No growth
  • Adhesion in Peel to Concrete 8.3 lbs/in width
  • Moisture Vapor Transmission ASTM E96 0.76 Perms —–
  • Crack-Bridging ASTM E836 1/8″ opening @ 77°F Pass (No rupture)
  • Hydrostatic Resistance ASTM D751 Procedure B Pass


  • School Locker Rooms and Restrooms
  • Plant Locker and Shower Rooms
  • Pool Decks
  • Kitchens and Bathrooms
  • Patios and Balconies
  • Shopping Malls
  • Stadium Concessions

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Product Technical Data Sheet:


Installation Video

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