PlaneMix S12 rapid

PlaneMix S12 rapid

Slump-free smoothing and repair mortar

  • For smoothing, repairs and building slopes
  • For substrates, such as concrete, ceramic tiles and timber
  • For interior use in dry and wet rooms
  • Easy to apply both to wall and floor
  • Adjustable consistency
  • Foot traffic after only 1 hour
  • Installation of floor coverings after 2 hours
  • Extended coverage
  • Thicknesses, min. up to 12 mm

Product calculator

Product facts


Grey, fast-setting, polymer modified powder on the basis of aluminous cement. Applicable by trowel.




For smoothing/straightening: approx. 1.3 kg per m² /mm thickness.

For thicknesses exceeding 5 mm, sand can be added in a dosage corresponding to grain size

Kiln dried sand, grain size
Dosage for 20 kg PlaneMix S12 rapid
Grain size: 0-2 mm
4 kg
Grain size: 0-4 mm
6 kg
Grain size: 0-8 mm
10 kg


Available in 5 kg and 20 kg PE lined paper bags.



Expected Result



Surface preparation

Fixing dowels





Alfix A/S H.C. Ørsteds Vej 11-13 DK-6000 Kolding
Declaration of performance
No. 37
DS/EN 13813 CT-C30-F7

Alfix PlaneMix S12 rapid
Cementitious screed
material for use interally
in buildings.

Reaction to fire A2fl-s1 Release of corrosive
Water permeability NPD Water vapour permeability NPD
Compressive strength C30 Flexural strength F7
Wear resistance NPD Sound insulation NPD
Sound absorption NPD Thermal resistance NPD
Chemical resistance NPD    

Tile fixing

Tile fixing



Technical data

Working temperature

+5°C - +25°C

Working time

Aprox. 20 min. at +20°C

foot traffic

After 1 hour at +20°C

Full Strenght

After 7 days at +20°C

Compression strength

25 - 35 N/mm²

Shelf life

Min. 6 mdr. months in unopened bag

How to use


Concrete subfloors, max humidity 95% RH.
Gypsum plaster, ceramic tiles, terrazzo, and timber floors.

For further information and details, please contact our Technical Services Dept.

Surface preparation

The surface should be dimensionally stable, sound, clean and free from dust and laitance. Residues from grease or soap can be removed with Alfix Deep Cleaner.

To remove laitance or roughen smooth surfaces, use mechanical preparation, such as sanding or grinding, and vacuum subsequently.

All surfaces should be primed with Alfix PlaneMixPrimer. Use primer in accordance with type of substrate.

Ensure a room temperature of min. +10°C while working. Allow primer to dry before commencing further treatment.

How to use

Add 0.2-0.3 litres of clean cold water per kg bag of powder depending on job and consistency. Pour water into a clean container and sprinkle in powder while stirring continuously. Mix until a lump-free and smooth consistency is obtained.

Alfix PlaneMix S12 rapid offers easy application and good workability when using straight steel trowel. Working time is approx. 20 minutes at +20°C.

As soon as the mortar starts to set, it can be formed, smoothened, and finished up with float, sponge or felt slightly wet.
Should grinding or sanding be required, allow 2 – 24 hours after application. Exposure to chair castors, min. thickness: 1 mm NB!
Do not mix larger quantities than can be applied within the working time stated. Additional water should not be added to repair mortar already starting to set.

Note that the temperature of mixing water will influence working time/pot life.
Over dosage of water will reduce strength and may produce laitance. Protect from draughts, direct sunlight, and heat.

Wet room usage requires installation of tanking system.
Close broken packaging carefully after use and use the rest within the shortest possible time.


Tools and tiles should be cleaned with water before the repair mortar sets.

Cement-based products harden when mixed with water, hence do not pour surplus PlaneMix into the drain system.

January 2021

Happy New Year! Team Alfix is back from Christmas holidays and ready to serve our good Scandinavian customers.

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