Adhesive CERESIT CT84 850 ml for polystyrene and mineral wool boards

Ceresit CT 84 is a polyurethane adhesive in an 850 ml cartridge formulated for fixing polystyrene (EPS/XPS) and mineral wool insulation boards in external thermal insulation composite systems (ETICS) and similar applications. It is suitable for bonding insulation boards to substrates such as wood, OSB, glass, bitumen, ceramic brick, concrete, coated and galvanized sheet metal, dry aerated concrete and dry masonry. Approximately two hours after application the boards can be levelled and mechanically anchored, and the reinforcing coat (for example Ceresit CT 85 or CT 87) can be applied.

Advantages

CT 84 delivers coverage up to about 10 m² per cartridge, which is significantly higher than traditional cement-based adhesives, and offers improved bond strength. The adhesive allows anchoring after about 2 hours, accelerating insulation works and enabling faster progress when used in combination with Ceresit Ceretherm systems. Its thermal behaviour is closer to that of insulation materials than cement mortars, and the product formulation contains metal spheres that reduce the formation of large air bubbles, ensuring high homogeneity of the adhesive.

Suitable for

• Bonding EPS and XPS polystyrene boards to external walls
• Fixing rigid mineral wool insulation boards
• Insulation works on wood, OSB, concrete, brick, glass, bitumen and coated or galvanized metal sheets
• Use in ETICS / facade insulation systems, including multi-layer insulation (“insulation on insulation”)

Key specifications

• Packaging volume: 850 ml cartridge
• Approximate coverage: up to 10 m² per cartridge (depending on application method)
• Suitable substrates: wood, OSB, glass, bitumen, ceramic brick, concrete, coated and galvanized sheet metal, dry aerated concrete, dry masonry
• Curing/anchoring time: approximately 2 hours before levelling and mechanical anchoring

How to use

Shake the cartridge vigorously for several seconds, remove the valve cap and screw the cartridge into a suitable gun with the valve facing upwards. Keep the gun valve closed until ready to dispense. Open the gun valve and apply the adhesive by pressing the gun trigger while holding the cartridge upright and maintaining an appropriate distance between the gun and the board to ensure correct bead formation. Before fixing EPS boards, secure starter rails. For additional insulation layers, apply the adhesive around the perimeter of the board about 2 cm from the edge and in one continuous bead across the centre, parallel to the longer sides. When bonding base insulation boards, apply the adhesive in five vertical beads parallel to the shorter sides, about 2 cm from the edge. After pressing the board to the wall, hold it in place and lightly press along the board with a long float; surface evenness can be adjusted within about 20 minutes after fixation.

Usage recommendations

Use CT 84 as part of Ceresit Ceretherm systems for faster installation and reliable bond performance; follow substrate preparation and manufacturer safety and handling instructions. Apply and cure at temperatures recommended by Ceresit for polyurethane adhesives to ensure proper adhesion and performance.