Hyperseal Expert – 150

HYPERSEAL®-expert-150 is a novel low modulus expansion joint sealant, especially formulated to ensure bubble free cure even at very high temperature and humidity climatic conditions. The product displays excellent thixotropy allowing its use even in very large expansion joints.

It cures by reaction with atmospheric humidity to produce a joint sealant with a 50% joint movement accommodation factor and excellent adhesion on substrates traditionally problematic for PU sealants, e.g. glass, aluminum, steel, polycarbonate, etc.. The extrusion rate and tooling of the sealant remain the same throughout a very wide range of temperature and humidity conditions.

Recommended HYPERSEAL®-expert-150 joints in:

• Inside concrete,
• Expansion concrete plates,
• Precast panels,
• Brick and block work,
• Water tanks and swimming pools,
• Metal frames,
• Aluminium windows and panels,
• Irrigation channels,


Not recommended for:
• Direct application on unsound substrates.
• Highly porous substrates, dusty surfaces or poorly compacted concrete, must have their porous bond area surfaces thoroughly sealed to avoid the possibility of air bubbles being blown into the uncured sealant if the substrate temperature rises.


• No bubbling/swelling upon curing in difficult climatic conditions.
• Excellent Thixotropy
• Excellent adhesion on almost any type of surface, with or without the use of special primers.
• Excellent extrusion, tooling and storage stability over wide range of climatic conditions.
• Excellent chemical resistance, suitable for sealing joints in swimming pools and chemically treated water.
• Low modulus, joint movement accommodation of 50%.
• Micro organism and fungus resistant.
• Excellent heat resistance, suitable for application where exposure to temperatures >60°C
• Resistance to cold: The sealant remains elastic even down to -40 °C


Clean the joint thoroughly, and ensure there is no oil, grease or wax contaminants, silicone remains should be removed. In the case of application on very porous substrates, we recommended using a primer for total adhesion is Geodesmo50. Apply backing material such as open cell polyurethane or a closed cell polyethylene backing rod. Backing cord application is important as it ensures that the correct width to depth ratio is achieved and it provides a firm backing against which the sealant which can be tooled off. Slide the sealant into the applicator gun, cut off the very end of the sealant packaging and fit the gun with the nozzle that has been cut to deliver the right bead size. Extrude the expansion joints sealant into the joint ensuring that no air is trapped in the joint. Tooling is recommended immediately after the application of sealant.

The ratio width to depth should be 2:1 subject to a minimum depth of 10mm

Available in: Grey, White, Black and Terracotta.

Download Datasheet