Applying Joint Filler

What is Joint Filler?

This fantastically versatile filler is specifically designed to be compatible with the Cemher microcement systems.  It sets hard and sands easily, for quick and easy preparation of surfaces for microcement.

It can be applied directly to all absorbent and non-absorbent surfaces. Thanks to its superior adherence it can even be applied directly onto tiles to fill grout lines.

Joint Filler is incredibly quick drying.  It is generally ready for microcement to be applied within around 12 hours, drying times do depend on fill depth, temperature & ventilation.

Joint Filler is the ideal for filling:

• Grout lines between tiles
• Joins between boarded floors and walls, including plaster boards, cement boards, tile on boards & composite timber boards
• Screw holes
• Small voids in substrates
• Small voids in concrete, screeds & self-levellers

Applying Joint Filler

Joint Filler is pre-mixed and ready to use.  It can be applied directly from the tub and has an unlimited working time.

Mix thoroughly with a mixer on a cordless drill.  If it still feels stiff, you can add up to 10% water to loosen & mix further.  That’s a maximum of 500ml per 5kg.

Use a trowel or scraper to fill joins and voids in the substrate. For a stable surface, be sure to fill the voids completely, there should be no air pockets under the surface. Trowel flat to remove the majority of the excess whilst wet, to avoid too much sanding.

Once dry, sand the surface until it is completely flat and well consolidated across the area.

Occasionally, the Joint Filler may shrink a little into the void when drying.  If this occurs, apply additional coats until the surface is completely flat.