Kiilto Highflex S2 DF
Tiling adhesive

A dust-reduced, very light, white tiling adhesive with good deformation properties. Ideal for installing e.g. glass mosaic, natural stone such as marble, sauna stove back panels and pre-fabricated steel bathrooms. C2TES2. Also for exterior applications. Cementitious.

Special features

  • white, dust reduced, light to apply, economical, good deformation properties, heat resistance + 100 °C
  • sauna stove back walls, ceramic tiles, glass mosaic, stones and marble
  • coverage 0.8-1.1. kg/m²
  • grouting: walls 12 h, floors 24 h
  • for interior and exterior areas




Kiilto Highflex S2 DF is an almost white, non-sagging and very economical cementitious adhesive with lightweight filler for the setting of ceramic tiles, glass mosaic, as well as marble and stone. Good deformation properties. The new, low-dust technology significantly reduces the amount of dust during mixing. Suitable tiling substrates include, e.g., vinyl, paint, glazed tile, clinker and common aggregate surfaces as well as gypsum and fibre cement-board treated with Kiilto waterproofing membrane or Kiilto Kosteussulku moisture barrier. If using on hot surfaces, e.g., fireplaces or stove back panels (in private saunas), the maximum temperature is +100 °C. Consider the need for expansion joints; the tiling must be done at normal room temperature. Jointing can be done without a joint string. Underfloor heating must be switched off approx. 24 hours before starting the tiling work. Suitable for interior and exterior use.

The surfaces to be tiled must be clean and free from dust. Remove water-soluble smoothing and levelling compounds. Dry and absorbent surfaces must be moistened (excl. boards). When tiling on vinyl, paint, tile and clinker substrates:

- ensure that the surface is solid and strong for tiling
- ensure that the surface to be tiled adheres properly to its own substrate
- remove wax, grease and dirt with alkali detergent and rinse well
After the surface has dried, sand it, if necessary, and then remove the sanding dust.

When tiling on paint or PVC-coated steel sheets (e.g., pre-fabricated steel bathrooms):

Any wax, grease or dirt must be removed from the surface, that is going to be tiled, with alkaline cleaner and rinsed thoroughly. After the surface has dried, sand it, if necessary, and then remove the sanding dust. Walls are primed with undiluted Kiilto Fix Primer (designed for vertical surfaces).

Notching of trowel
Notching of trowel
Package Size EAN Code
2,5 kg 6411513947050
10 kg 6411513947104
Application temperature

Optimal +18–20 °C, minimum +5 °C

Bond strength

above 1.0 MPa (EN 1348)

Classifications and certificates

C2TES2 (EN12004), M1


approx. 1.1 kg/m² applied with a standard notched trowel (notching: 6 mm x 6 mm x 6 mm) 6 mm)
approx. 0.8 kg/m² applied with a mosaic trowel (notching: 4 mm x 4 mm x 4 mm)


above 5.0 mm (EN 12002)

Fire class


Frost resistance


Max. grain size

0.3 mm

Mixing ratio

approx. 4.5 l water / 10 kg powder (walls)
approx. 5.0 l water / 10 kg powder (floors)

Open time

above 0.5 MPa / 30 min (EN1346)

Package sizes

2.5 kg plastic container, 10 kg bag


below 0.5 mm (EN 1308)


Unopened package in a dry place 1 year.

Substrate humidity

concrete < 90 % RH


Polymer-aluminate cement-lightfiller-quartz powder

Working time

working time approx. 2 hours after adding water

Instructions for use

Strew Highflex S2 DF powder slowly while stirring in cool, clean water until a smooth mass is formed. Let the mix mature for approx. 10–15 min. and then remix gently once before use. Apply the adhesive to the surface by pressing firmly and comb with a notched applicator an area that can be tiled within 20 minutes. Press the tiles firmly onto the surface and tap into position immediately. Tiles' position can be adjusted for 15 minutes. It is recommended to randomly lift tiles during the application to ensure sufficient coverage of tile backs (glazed tiles 70–75% and clinker 80–90%). When tiling outdoor areas, the coverage of tile backs must be 100 %. To make sure that you get adequate adhesive coverage under the tiles, the trowel should be chosen according to the tile size and the tiling surface.

Remove fresh adhesive stains with water and a damp cloth. Dried adhesive can only be removed by mechanical means.

Walls can be jointed with Kiilto Saumalaasti after 12 hours of the tiling having been carried out; floors after 24 hours. Allow the tiling to dry for a week before proceeding to use as normal. Low temperature and high air humidity will retard the curing and drying process.

Edges of panel and board walls, joints between wall and floor tiling and other movement joints should be jointed with Kiilto Saniteettisilikoni.

Suitable for correcting minor irregularities on the substrate prior to tiling. For corrections of several millimetres, we recommend Kiilto wall plasters and floor levelling compounds.

Additional information

The information given in this product data sheet is based on our tests and our practical knowledge. The technical data is defined in standard conditions. Variations in local working conditions and methods will affect the product performance and result. We guarantee the high quality of our products according to our Quality Management System. No liability can be accepted from incorrect use of the product or prevailing conditions, over which we have no control. Thus, we cannot be held responsible for the final result. The correct use of the product presupposes that the user has made him/herself aware of the contents of the working instructions and procedure guide, if provided.

Environment and safety

Avoid unnecessary skin contact and exposure with the fresh product, use safety gloves. Refer to material safety data sheet. For information on product and package disposal, go to