Highly elastic sealant

Highly elastic sealant for movement joints in ceramic tilings, marble, natural stone, etc. and for use on exterior facades.

  • For wet rooms and sanitary installations
  • Prevents growth of fungus and moulds
  • No discolouration of acid sensitive surfaces, such as marble
  • Suitable for facades
  • Fast curing
  • Colour stable - no yellowing
  • Non-corrosive to metals

Product calculator

Product facts


High-elastic, one-component sealant on the basis of silicone rubber .
Cures neutrally when exposed to air humidity


Available in colours to match cement-based Alfix Cerafill range: brilliant white, grey, pale grey, steel grey, graphite, anthracite, black grey, light beige and jura beige. Colour swatches available on request.



Joint dimension B x D
Linear metres per cartridge
6 x 3 mm
ca. 16,0
8 x 4 mm
approx. 9,0
10 x 5 mm
approx. 5,5
15 x 7 mm
approx. 2,5


Available in 300 ml cartridges.


Due to neutral curing, Alfix M-Silicon will not cause any colour alteration of acid-sensitive materials, such as natural stone and hence, the product is very suitable for marble, granite, travertine, etc.
Also ideal for sealing facades with ceramic tiles as the product does not attract dirt.
Alfix M-Silicone retains elasticity and produces a long life weather- and waterproof joint resistant to mildew (sanitary type).


Expected Result


Particularly suitable for expansion joints in ceramic surfaces, sealing around pipe passages, and sanitary installations.
Excellent adhesion without priming to glass, ceramic tiles, marble, natural stone, enamel, metals, painted surfaces, and varnished wood.


Surface preparation

Fixing dowels






Alfix A/S H.C. Ørsteds Vej 11-13 DK-6000 Kolding alfix.com

DOP No. 24

EN 15651-1: F-INT-EXT-CC
EN 15651-3: S

Alfix M-Silicon
Sealant for facade for interior and exterior application and for joints in sanitary areas

Reaction to Fire (EN 13501) Class E Release of chemicals dangerous to the environment and health See product safety sheet on www.alfix.com
Conditioning: Method A (ISO 8340). Substrate: Glass without primer, aluminium without primer.
Water tightness and air tightness
Resistance to flow (ISO 7390) ≤ 2 mm Sectant tensile modulus at -30°C (ISO 8339) ≤ 10%
Loss of volume (ISO 10563) ≤ 10% Tensile properties at maintained extension at -30°C (ISO 8340) Pass
Evaluation of the action of microorganisms (ISO 846) 1    

Tile fixing

Tile fixing



Technical data

Working temperature

-20°C - +40°C


1.33 kg/litre

Formation of skin

10 – 30 minutes

Curing speed

approx. 1 mm/day

Temperature resistance

-40°C - +150°C


approx. 24 shore A

Maximum movement

+/- 25% of original joint width


approx. 7%

Shelf life

Min. 18 months in unopened cartridges. Store cool.

How to use


Surface preparation

Surfaces should be clean and dry and free from dust, grease and oil.
For degreasing use acetone or ethanol.
Shining metals or plastics should be sanded.
For sealing tiled surfaces, joints should be clean down to original substrate.
Deep joints should be filled with a backing material, such as polyethylene foam, to support sealant and prevent adhering to bottom of the joint.

How to use


Use masking tape to protect tiles.
Fill joints completely using appropriate gun. Finish off within 15 minutes by smoothing using a damp tool, such as smoothing kit or joint nail.
Remove any masking tape immediately after smoothing.



Uncured sealant: Acetone
Cured sealant: mechanical

December 2017

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