Brands and countries


  • Specifically for renovation on wooden subfloors
  • Very high mechanical resistance with no shrinkage
  • Heavy duty thickness


  • Color: grey
  • Working time: 20min
  • Walk on time: 5h
  • Coverage: 1,5 kg/mm/ m²
  • Curing time: 
    • Tiling: 24h
    • PVC, linoleum, rubber: 48-72h
    • Floor paint: 48-72h


Measure 6 liters of clean, cold water into a clean mixing bucket. Gradually add the bag of Bostik SL C780 FLEX to the water, whilst continually mixing with an electric drill and mixing paddle until a smooth lump-free mixture is obtained. This will normally be achieved after 2 minutes. The mixture will retain its self-smoothing capability for approximately 20 minutes under normal conditions. Pour the mixed material onto the prepared substrate to a thickness between 1mm and 30mm. Using a smooth edge stainless steel trowel, smooth over the wet product to gain the desired thickness and smoothness. A pin level may be used to assist in gaining the required depth. Use a spiked roller to remove any trapped air and flow lines, to give a uniform surface appearance.

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