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    ​​​​​​​​​​MasterSeal M 645 - One Component, High Performance, Liquid Cold-Applied Polyurethane Waterproofing Membrane

    ​​​What is MasterSeal M 645?

    ​MasterSeal M 645​ is a unique, single-component, liquid-applied polyurethane membrane for the waterproofing and protection of concrete, metal, and fiber-based cement substrates. 

    ​How do you apply MasterSeal M 645? 

    ​MasterSeal M 645 can be easily applied in thick layers without bubbles. It forms a hydrophobic, elastic, seamless membrane without joints to protect old and new structures. 

    Download the MasterSeal M 645 Technical Data Sheet

    Where can MasterSeal M 645 be used?

    ​MasterSeal M 645 is a waterproofing or damp-proofing membrane for concrete protection with excellent crack-bridging properties. It is suitable for new and refurbishment projects and is recommended for use in: 

    • ​Waterproofing for exposed roofs with topcoat 
    • Balconies, Terraces, Podium, Roofing, Pedestrian Traffic areas
    • Light roofing made of metal or fibrous cement 
    • Refurbishment on existing bitumen sheet membrane
    • Protection of polyurethane (PU) foam​

    ​How can you benefit from MasterSeal M 645?

    ​The benefits of MasterSeal M 645 include:

    • High thickness build-up per layer
    • Improved workability - thick layers are easily applied without bubbling 
    • Simple application by roller, brush, or airless spray system
    • Highly elastic with crack-bridging properties
    • Excellent mechanical properties with no reinforcement required except for detailing 
    • High-temperature resistance of up to 80 °C
    • Seamless membrane without joints​

    Download the MasterSeal M 645 Technical Data Sheet

    System build-up for concealed roof

    ​MasterSeal M 645 can be used as part of a system for concealed roofs: 

    System build-up for MasterSeal M 645 for concealed roof

    ​​​System build-up for exposed roof

    ​MasterSeal M 645 can be used as part of a system for an exposed roof:

    System build-up for MasterSeal M 645 for exposed roof


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