Causes & Preventive Measures

• Do not use expired coatings or coatings that have exceeded the usable time after mixing.
• Insufficient mixing of two-component materials (either manual or mechanical mixing). Ensure thorough blending of mixed materials.
• Mixing containers are contaminated. Thoroughly clean mixing buckets before use.
• Incorrect material proportioning.

Causes & Preventive Measures

• Completely clean the substrate surface prior to coating application.
• Verify the substrate has adequate strength; it must not sand off, peel or become loose.
• No standing water is allowed on the substrate for water-based coatings.
• The substrate must be fully dry for solvent-based coatings.
• Apply a prime coat for the first layer of coating.

The substrate at blister locations contains excessive moisture, or the substrate surface is uneven. Poor adhesion at depressions on the substrate or residual moisture inside the membrane will generate water vapor and internal air pressure as the ambient temperature rises, resulting in blistering of the waterproof membrane.

• Linear cracking at the end joints of roof panels, caused by substrate deformation, thermal expansion and contraction under temperature variation, and uneven settlement of the building.
• Uneven laying of thermal insulation layers and inconsistent thickness of cement mortar leveling courses.Cracks in the leveling course due to substrate movement will further lead to irregular cracking of the waterproof membrane.
• Insufficient lap width or defective edge termination of the membrane, resulting in tensile cracking.
• Membrane cracking induced by aging and crazing, rupture of blisters, physical damage, inferior material quality, low elongation or poor tensile strength of the membrane.
• Low ambient temperature in winter may cause brittle cracking of the membrane.
• No additional membrane strip laid flat at the end joints of roof panels. The membrane lacks expansion allowance and cracks when roof panels shift.

• Evenly apply primer on the substrate before membrane installation. Lay the membrane promptly after the primer is fully dry.
• Completely remove the release film on the adhesive side of the membrane before laying.
• Slightly tension the high polymer modified bitumen waterproof membrane during rolling installation (avoid excessive slack). Fully expel trapped air beneath the membrane and roll firmly to ensure solid adhesion.

• Apply uniform heat across the full width of the membrane. Avoid overheating to prevent damage to the membrane carrier layer.
• Roll and lay the membrane immediately after hot melting. Roll thoroughly to exhaust air, ensuring the membrane is flat, tightly bonded and wrinkle-free.
• Stop rolling when a small amount of hot-melt adhesive extrudes from the membrane edges. Immediately scrape and seal the joints with the extruded adhesive.
• After the completion of the entire waterproof layer, seal all lap joints with sealant.

• Polymer Waterproof Membrane
• Bitumen-Based Polyester Carrier Waterproof Membrane

• High Polymer Modified Bitumen Waterproof Membrane
• Synthetic Polymer Waterproof Membrane

• Improve the low-temperature performance of bitumen compound.
• Act as a fluxing agent.
• Adjust the viscosity of bitumen compound to facilitate manufacturing and forming.
• Excessive addition will impair temperature sensitivity and bond strength of the bitumen compound.

Modified bitumen is produced by blending base bitumen with polymer materials such as SBS and APP via chemical, physical and mechanical methods. The blend forms a continuous network structure or uniformly dispersed phase. This composite material inherits superior properties of polymers including elasticity, wear resistance, aging resistance, corrosion resistance and weatherability, thus optimizing the inherent performance of original bitumen.