STS Mega Strength PU Adhesive — Fast Set | 310ml

STS Mega Strength is a fast-set polyurethane adhesive formulated for bonding STS TG4 Construction Board. It is the recommended adhesive for TG4 installation, providing an exceptionally high bond strength that secures boards firmly. The water-free PU formulation expands slightly on application to fill small voids and surface irregularities beneath the board — ensuring full contact between the board and subfloor without excessive foam bleed — and cures to a 100% waterproof bond. 

Set time is 5 minutes, allowing boards to be positioned and held briefly before the adhesive grabs — significantly faster than standard construction adhesives and important when installing across large floor areas where working time needs to be managed efficiently.

Applications

• Tongue and groove joints — suitable for bonding the tongue and groove joints between boards, locking the floor panel assembly together and eliminating movement at the board edges.

Product Benefits

• 5-minute set time. Grabs and holds within 5 minutes of application, allowing the installation to progress without extended wait times between board placement and the next installation step.
• Water-free formulation — controlled expansion. Standard PU adhesives react with moisture to generate foam, which can cause excessive bleed and lift boards away from the substrate if not managed. The water-free formulation in STS Mega Strength expands only enough to fill small gaps, maintaining flat board-to-subfloor contact without excessive foam.
• 100% waterproof bond. Fully waterproof when cured, making it suitable for installation in areas subject to moisture exposure.
• Exceptionally high bond strength. Polyurethane adhesives deliver significantly higher bond strength than standard dispersion or solvent-based construction adhesives, providing a permanent, rigid connection between the board and subfloor.
• 310ml cartridge tube. Standard cartridge format compatible with a standard skeleton gun — no specialist application equipment required.