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
System build-up for concealed roof
MasterSeal M 645 can be used as part of a system for concealed roofs:
System build-up for exposed roof
MasterSeal M 645 can be used as part of a system for an exposed roof:
![]()
Downloads
Bellandur Lake project reference
Brochure - Construction Solutions for Power and Industry
Brochure - Introduction to Master Builders Solutions