LetFix Universal

Flexible tile adhesive - Light
- For ceramic and quarry tiles, mosaics and natural stone
- For large-sized tiles and porcellanato tiles
- Fixing of insulating plates
- For interior and exterior use
- Extra high yield
- Extra smooth with light-weight workability
- High initial grab
- Approved for wet rooms
- Suitable for underfloor heating
- Bed thicknesses up to 5 mm
Product facts
Product
White, cement-based powder containing light fillers and high-performance polymer modifiers.
Colours
Coverage
Coverage
Packaging
Available in 3.5 kg and 18 kg PE lined paper bags.
Features
Generel
Expected Result
Application
Waterproofing
Surface preparation
Fixing dowels
Finishing
Sealings
Flooring
Precautions
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Alfix A/S H.C. Oersteds Vej 11-13 DK-6000 Kolding alfix.com 11 |
Declaration of performance No. 1 |
EN 12004:2007+A1:2012 Alfix LetFix Universal Improved cementitious adhesive for internal and external tiling |
Reaction to fire | NPD | Release of dangerous substances |
See material safety data sheet www.alfix.com |
Bond strength: Initial tensile adhesion strength |
≥ 1,0 N/mm² | Durability, tensile adhesion strength after heat ageing |
≥ 1,0 N/mm² |
Durability, tensile adhesion strength after water immersion |
≥ 1,0 N/mm² | Durability, tensile adhesion strength after freeze/thaw cycles |
≥ 1,0 N/mm² |
Tile fixing
Tile fixing
Tests
DS/EN 12004 - DS/EN 12002
Surfaces
Technical data
+5°C - +30°C
1.35 kg/litre (mixed with water)
20 – 30 minutes
5 hours at +20°C
24-48 hours at +20°C
7 days at +20°C
1.0 – 2.0 N/mm²
C2 TE S1
Min. 12 months in unopened bag
How to use
Surfaces
Cement/sand rendering, brickwork, aerated concrete.
Screed, with or without underfloor heating, older than 14 days.
Light-weight concrete, max. moisture content 8%.
Flooring containing cement-based levelling compound.
Anhydrite floors, max. residual moisture 0.5%.
Concrete in situ and precast units/slabs, older than 6 months.
Paper-faced plaster boards, fibre-reinforced plaster boards.
Existing tiles, terrazzo.
Vinyl and paint on concrete.
Alfix Sealing Membrane.
Plaster, wood, existing tiles, vinyl, and paint are not considered suitable surfaces for exterior use or in areas exposed to frequent or permanent water.
Surface preparation
The surface should be dimensionally stable, sound, and clean. Free from laitance, grease, and dust. There should be no blooms or crack formations. Residues from grease or soap can be removed with Alfix Deep Cleaner. Ensure that paint is sufficiently adhering and non-flaking. Sand/Matt vinyl and paint with the appropriate sandpaper and apply a thin contact layer of Alfix LetFix Universal.
Straightening of lumps and unevenness of up to 5 mm can be carried out using Alfix LetFix Universal.
On absorbent, moisture sensitive interior surfaces, such as aerated concrete, gypsum plaster, plaster boards, and anhydrite floors, apply Alfix Primer (Sealing Primer) or Alfix PlaneMixPrimer
For exterior use, apply a thin contact layer of Alfix LetFix Universal.
How to use
Add approx. 0.4 – 0.5 litres of clean, cold water per kg powder depending on whether to use as non-slip wall adhesive or pourable floor adhesive.
Apply Alfix Letfix Universal to the surface with a notched trowel, using the straight edge to spread out adhesive and subsequently the notched edge to produce a ribbed bed.
Fix tiles within 20-30 minutes by pressing them firmly into position in the wet adhesive with a slight twisting action. When fixing mosaics, a firm tap is required.
Ensure complete adhesive coverage!
For tile sizes exceeding 60 X 60, apply adhesive to both tiles and surface to ensure solid bedding leaving no voids (buttering/floating method).
For exterior use, e.g. stairs and facades, regardless of tile size, always apply buttering/floating method.
NB!
Large-sized tiles and natural stone may call for extra attention.
Alfix LetFix Universal is based on white Portland cement, which prevents colour difference at bright natural
stone. However, this can not be guaranteed under all conditions. Hence, for receptive and moisture
sensitive stones it is recommendable to trial a small area to ensure that tile and adhesive are compatible.
Additional water should not be added to adhesive already starting to set. Note that the temperature of
mixing water will influence setting time.
Repositioning of tiles should be done within approx. 20 minutes after fixing, depending on substrate and
tile absorbency.
Switch off any underfloor heating.
Cleaning
Clean adhesive residues from tools and tiles with water before the adhesive sets. Cement-based products harden when mixed with water, hence do not pour surplus adhesive into the drain system.