S1 class flexible adhesive for large format tiles, marble, natural stone and areas subject to thermal movement — deformability of ≥2.5mm for all demanding installations.
What Makes Flex
Stand Out
S1 class flexible adhesive for large format tiles, marble, natural stone and areas subject to thermal movement — deformability of ≥2.5mm for all demanding installations.
Deformability ≥2.5mm — absorbs differential movement between tile and substrate, preventing cracking and debonding.
Specifically engineered for marble, travertine, onyx and sensitive natural stone — won't cause staining or discolouration.
Handles large format tiles up to 1200×1200mm — high initial tack prevents slippage of heavy format tiles.
Certified for use over underfloor heating systems — S1 flexibility absorbs thermal expansion and contraction.
Suitable for exterior facade cladding with large format tiles — handles wind-load induced movement.
Thixotropic consistency prevents slippage on vertical surfaces — ideal for large-format wall tiles.
Low VOC formulation suitable for interior spaces — safe for sensitive environments.
Long open time allows correct positioning and adjustment of large format tiles and natural stone slabs.
Technologies
Transverse deformation ≥2.5mm — handles movement in substrate and tile
White formula won't stain sensitive light-coloured natural stone
High tack prevents slippage of large, heavy format tiles on walls
S1 flexibility handles thermal cycling of underfloor heating systems
Where Flex Performs
Marble, travertine, onyx and sensitive natural stone — floor and wall
Tiles over 600×600mm — up to 1200×1200mm on floor and wall
All types of underfloor heating — electric and hydronic systems
External facade tiles — handles wind load and thermal movement
Tiles over timber floors and wooden substrates with inherent movement
Pool deck tiles and water feature surrounds with thermal movement
How to Use Flex
- Cured concrete and screed (sound and flat)
- Existing sound tile surfaces
- Marine plywood and timber floors (stable, free from flex)
- Cement board over steel frame
- Underfloor heating systems (switch off 48h before tiling)
- All natural stone — marble, travertine, granite, slate, onyx
- Large format vitrified and porcelain tiles to 1200×1200mm
- Agglomerated and recomposed stone slabs
- Mosaic and glass mosaic tiles
- Surface must be flat to within 3mm over 2m (key for large format)
- Remove all contamination
- Prime timber and plywood surfaces with Wallnut primer
- For underfloor heating: switch off 48h prior, restart 24h after grouting
- Mix powder with clean water using slow-speed stirrer
- Achieve smooth, lump-free consistency
- Slake 5 min and re-stir
- Pot life: follow label — do not re-temper
- Use 6mm, 10mm or 12mm square notch trowel (tile-size dependent)
- Always back-butter natural stone and large format tiles
- Achieve minimum 80% coverage on all installations
- Use appropriate C&L grout after cure
Ideal working temperature +5°C to +35°C. Avoid applying in direct sunlight or on very hot surfaces.
Work within the pot life after mixing. Use T class extended open time for large or complex layouts.
Match notch trowel size to tile format — 6mm for small tiles, 10–12mm for large format tiles.
Lift a tile to verify adhesive coverage — minimum 65% for floors, 80% for exterior and wet areas.
Do not pre-wet the substrate with water. Ensure surface is clean, dry and free from contamination before applying adhesive.
Technical Data
Coverage varies depending on substrate flatness, tile format and application method. Use the Product Calculator for exact estimates per project.
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