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Hydrotech Green Roof

Monolithic Membrane 6125 - Waterproofing

Monolithic Membrane 6125® (MM6125®) is a thick, tough, flexible, self-healing membrane for use in waterproofing. MM6125 is a special formulation of refined asphalts and synthetic rubbers. MM6125 has been successfully used worldwide by leading architects, engineers and owners on all types of horizontal and vertical structures including plazas, parking decks, planters, tunnels, bridges, mud slabs, foundation walls and roof areas...establishing an unbeatable track record of 60 years.


    Typical Waterproofing Applications

    Fabric Reinforced (FR) Assembly
    Vertical Waterproofing
    Asphalt Overlay
    Split Slab Construction

    MM6125 has many unique characteristics:

    • MM6125 is a thermoplastic material - one component, 100% solids, NO solvents means no on-site cure failures, no two part mixing and no VOC restrictions.
    • MM6125 has a minimum 40% recycled content; validated by UL.
    • MM6125 conforms to all surface irregularities and bonds tenaciously to an acceptable substrate (i.e., concrete, steel, wood, etc.) eliminating lateral migration of water.
    • MM6125 is completely monolithic, no seams!
    • MM6125 is typically installed at 215 mils thick in the Fabric Reinforced Assembly. This is more than three times thicker than most other waterproofing membranes. Thickness is an important benefit in that MM6125 exhibits the ability to self-heal and better accommodate developing cracks in a concrete substrate.
    • MM6125 can be installed at temperatures as low as 0 °F (provided the substrate is clean, dry, free of snow and frost).
    • MM6125 detailing is simplified, with triple protection at all critical locations.
    • MM6125 is ideal for dead level installations; no slope required, just positive drainage.
    • MM6125 was developed to perform in a wet (submerged) environment.
    • MM6125 tie-ins from one days work to the next is easy, perfect for phased construction.

    One of the reasons MM6125 has been so successful in the market place is that MM6125 can only be installed by "trained" authorized Hydrotech applicators. MM6125 is sold direct, not through a distributorship.

    MM6125 Approvals/Certifications:

    • Manufactured under ISO 9001:2015
    • CAN/CGSB 37.50-M89 (Canadian General Standards Board)
    • Applicable ASTM Test Methods (American Society for Testing and Materials)
    • BBA Approval (British Board of Agrément)
    • UL Class A Classification (Underwriter Laboratories)
    • UL validation of recycled content (Underwriter Laboratories)
    • FM Approval (Factory Mutual)
    • Dade County, FL Approval
    • General Approval - City of Los Angeles
    • MEA Approval - City of New York

    If you should have any questions regarding Hydrotech assemblies or if we can be of any assistance on your next waterproofing or roofing project, please don't hesitate to contact us.

    MM6125 Physical Properties ChartShow




    Recycled Content

    UL Validated

    40% minimum

    Flash Point

    ASTM D-92, CGSB-37.50-M89

    500 °F (260 °C)*

    Low Temperature Crack Bridging Capability


    No cracking, adhesion loss, or splitting

    Water Vapor Permeability

    ASTM E 96, Procedure E, CGSB-37.50-M89

    1.6 ng/Pa(s)M², (0.018 perm)

    Water Resistance (5 days/50 °C)


    No delamination, blistering, emulsification, or deterioration

    Water Absorption


    0.22 g weight gain



    13.0 Joules

    Ratio of Toughness to Peak Load





    7.0 seconds

    Heat Stability


    No change in viscosity, penetration, flow or low temperature flexibility

    Low Temperature Flexibility ( - 25 °C)


    No delamination, flexibility adhesion loss, or cracking


    ASTM D 1191, CGSB-37.50-M89

    75.0 mm @ 77 °F (25 °C), 121.7 mm @ 122 °F (50 °C)


    ASTM D 1191, GSB-37.50-M89

    0.0 mm @ 140 °F (60 °C)

    Softening Point

    ASTM D 36

    180 °F (82 °C)


    ASTM D 1191

    1000 % minimum


    ASTM D 3407

    40% minimum

    Bond to Concrete @ 0 °F, (18 °C)

    ASTM D 3408


    Hydrostatic Pressure Resistance

    ASTM D-08.22, Draft 2

    100 psi (=231 foot head of water)

    Acid Resistance

    ASTM D 896 Procedure 7.1 (N-8)

    Pass 50% Nitric Acid, 50% Sulfuric Acid

    Salt Water Resistance (20% sodium carbonate and calcium chloride)

    ASTM D-896 similar

    No delamination, blistering, emulsification, or deterioration

    Fertilizer Resistance (undiluted 15/5/5 nitrogen /phosphorus/potash)

    ASTM D-896 similar

    No delamination, blistering, emulsification, or deterioration

    Animal Waste Resistance

    3 year exposure

    No deterioration

    Solids Content


    100% no solvents

    Shelf Life


    10 years (sealed)

    Specific Gravity



    1.23 ± .02

    45 °F more than the application temperature recommended by the manufacturer.