Sopro FAS 551 – Fibre Reinforced Self-Levelling Filler

Self-levelling, cementitious floor filler used to even out irregularities in timber and mineral substrates prior to flooring installation. A flexible, flow-applied, self-levelling, rapid-set, cementitious, fibre-reinforced surface filler used to even out irregularities in timber and mineral substrates, especially on refurbishment/renovation contracts. Appropriate for castor chairs and floor heating systems.Low-chromate to Regulation (EC) No 1907/2006, Annex XVII.

Sopro FAS 551 - Fibre Reinforced Self-Levelling Filler

Sopro FAS 551 – Fibre Reinforced Self-Levelling Filler

Floor-levelling compound for production of smooth, unbroken surfaces to receive any flooring type, e.g. ceramic tiles, natural stone coverings, carpeting, parquet, linoleum and PVC.  Suitable substrates include; old, rigid timber flooring, wood floorboards, grade V 100 G particleboard to DIN 68763; concrete;
cement screeds; board (e.g. gypsum plasterboard or gypsum fibreboard) subfloors.

Related Downloads

icon-pdf TDS Sopro FAS 551 – Fibre-Reinforced Self-Levelling Filler

icon-pdf SMET Professional Tiling Systems Brochure

icon-pdf Sopro FAS 551 – Fiber-reinforced self-levelling filler_Sustainability Datasheet

icon-pdf SMET Floor Screeds and Compounds Product Selector

NBSplus NBS Specification Clause

Benefits of Sopro FAS 551 – Fibre Reinforced Self-Levelling Filler

  • For 3 – 20 mm coat thicknesses (up to 40 mm when extended)
  • Self-levelling
  • Rapid-set
  • Fibre-reinforced and highly flexible
  • Pumpable
  • Suitable for floor heating systems
  • Particularly suitable on refurbishment/renovation contracts
  • EMICODE system of GEV (German Association for Control of Emissions in Products for Flooring Installation): EC1PLUS (“very-low-emission-plus”) rating
  • DGNB (German Sustainable Building Council): Top quality level 4, Line 8*
  • For indoor use

Technical Data for Sopro FAS 551 – Fibre Reinforced Self-Levelling Filler

Suitable Substrates Old, rigid timber flooring, wood floorboards, grade V 100 G particleboard to DIN 68763
Coat Thickness Not extended: 3 – 20 mm
Extended: for coat thickness upwards of 20 mm, can be extended using 0 – 4 mm graded silica sand (e.g. Sopro EEK 871 epoxy screed aggregate) by up to approx. 1/3 of prepared compound volume
Mixing Ratio Approx. 6.5 ltr water : 25 kg Sopro FAS 551
Take care to ensure exact proportioning of water
Flow table value 24.5 – 25.5 cm (Vicat ring to DIN 1164; size: internal diameter 65 mm at top and 75 mm at bottom, height 40 mm; on suitable, dry, clean glass plate)
Compressive Strength (28 days) C30
Flexural Strength (28 days) F7
Working life 20–30 minutes
Walkable After approx. 2 hours
Ready to receive floor covering Ready to receive ceramics and cast stone after 2 – 3 hours; natural stone after 24 hours. For elastic, textile, laminate, parquet and wood block floor coverings, maximum permissible moisture content (≤ 1.8% CM) must be confirmed by CM measurement over full screed cross-section prior to flooring installation. Empirical values for achievement of this – in the function of filler coat thickness, subject to application to dry substrate – are as follows:

– 3 – 5 mm coat thickness: after approx. 1 day
– 5 – 10 mm coat thickness: after approx. 5 days
– 10 – 20 mm coat thickness: after approx. 5 – 7 days

Application temperature From +5°C to +25°C (substrate, air, material)
Coverage Approx. 1.6 kg/m² per mm coat thickness
Shelf Life Approx. 6 months, subject to storage on pallet in dry conditions in original containers
Use Indoor only
Reaction To Fire Class A2fl -1
Apparent density Approx. 1.8 kg/dm³

*Based on DGNB (German Sustainable Building Council) criterion “ENV1.2 Local Environmental Impact” (2015 version).

Available in 25kg bags, 42 bags per pallet



SMET offer a wide range of Sopro compounds, CASEA binders, and filler for all your substrate needs, including UFH,  retro-fit and renovation