PlaneMix 80

PlaneMix 80

Fast-track screeding mortar

  • Screeding mortar for floors onto joisted timber, concrete, or terrazzo
  • For bonded or floating screeds and subfloor repairs
  • For interior use
  • Foot traffic after 3 hours
  • Ready to receive dense coverings after 24 hours
  • Ideal for rapid preparation of subfloor
  • Suitable for underfloor heating
  • Thickness: 20 - 80 mm

Product calculator

Product facts


Grey, fast-setting, polymer modified cement-based powder.
Applicable by trowel.
Grain sizes up to 5 mm.




Ca. 1700 kg pr. m3

Thickness in mm
Kg per m²
20 mm
Approx 35
50 mm
Approx 85
80 mm
Approx 135


Available in 20 kg PE lined paper bags.



Expected Result



Surface preparation

Fixing dowels





Alfix A/S
H.C. Oersteds Vej 11-13
DK-6000 Kolding 08
Declaration of
performance No. 15
DS/EN 13813 CT-C40-F6 Alfix PlaneMix 80
Cementitious screed
material for use interally
in buildings.
Reaction to fire A1 Release of corrosive
Water permeability NPD Water vapour permeability NPD
Compressive strength C40 Flexural strength F6
Wear resistance NPD Sound insulation NPD
Sound absorption NPD Thermal resistance NPD
Chemical resistance NPD    

NPD = No performance determined

Tile fixing

Tile fixing



Technical data

Working temperature

+10°C - +25°C


1.9 kg/litre (mixed with water)

Working time

Approx. 45 minutes at +20°C

Foot traffic

After 3 hours at +20°C

Floor covering

After 3 hours at +20°C


After 4 hours at +20°C

Floor covering

After 7 days at +20°C

dense coverings

After 24 hours at +20°C

Full strength

After 7 days at +20°C

Compression strength, 28 days

30 - 40 N/mm²

Bending tensile strength

5 - 7 N/mm²


Cohesion strength approx. 1.5 N/mm²

Shelf life

Min. 6 months in unopened bag

How to use


Wooden floor constructions onto existing timber joist systems in areas up to 6 m². Joist spacing: 600 mm.
Concrete with or without underfloor heating, existing tiles, or terrazzo for bonded or floating coating on screeds.

Surface preparation

The surface should be dimensionally stable, sound, clean and free from dust and laitance. For application on timber joisting apply rigid/hard insulation between joists and provide floating coat consisting of 2 layers of geotextile. Subsequently install reinforcement mesh, diameter 6 mm.
For surfaces requiring bonded coating, broom or brush the surface with a mixture of Alfix PlaneMixPrimer and Alfix PlaneMix 80 in the ratio 1:1.
Apply the mixture thoroughly by use of brush or broom and work it well into the surface.
Do not allow the slurry to dry before further treatment.
Ensure a room temperature of min. +10°C.

How to use

Add approx. 1.8 – 2.0 litres of clean cold water per 20 kg bag of powder. Use large mixing container, drum, paddle stirrer or electric drill and mix thoroughly for approx. 2 minutes until a semi-dry consistency is obtained.

Lay out PlaneMix 80 wet-on-wet onto the brushed surface and spread evenly. Upon compaction, level and render the surface by use of smoothing board/straight edge. If necessary, steel trowel the surface until it appears smooth and closed.

Application, rendering and trowelling should be done in one, ongoing work operation. Do not work over larger areas than can be completed within the 45 minutes working time stated.

Min. bed thickness – bonded screed on concrete: approx. 20 mm.

Min. bed thickness – floating screed: approx. 40 mm.


Additional water should not be added to screeding 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 cause crack formation.
Switch off any underfloor heating and allow 7 days before switching heating back on.
Application in wet rooms requires subsequent tanking with sealing membrane.
Tanking and tiling: 4 - 6 hours at +20°C
Dense coverings: 24 hours at +20°C
Levelling: Use Alfix PlaneMix S8 rapid or alternatively Alfix PlaneMix S12 rapid after 4 – 6 hours.


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

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

March 2018

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