Pumpable, self-levelling, rapid-set, cementitious surface filler. Used for the production of smooth, unbroken surfaces prior to installation of floor coverings, e.g. ceramic tiles, natural stone finishes, textile, elastic and parquet flooring.

For coat thicknesses between 3–40 mm. (Sopro FS 5 549 floor-levelling compound is recommended for thin-coat (≤ 3 mm) applications; Sopro FE 678 Rapidur® self-levelling screed is recommended for coat thicknesses > 40 mm.) Low-chromate to Regulation (EC) No 1907/2006, Annex XVII.

Features and benefits:

  • Pumpable.
  • Suitable for floor heating systems.
  • For indoor use only.
  • CE marked.

Suitable primers:

  • Sopro HE 449 bonding emulsion: For wet-on-wet application. Suitable substrates include: cement screeds, untreated concrete surfaces (three months old minimum).
  • Sopro GD 749 primer: All absorbent substrates, e.g. cement screeds, concrete/untreated concrete surfaces (three months old minimum).
  • Sopro HPS 673 special primer: All smooth, non-absorbent substrates, e.g. existing tile and terrazzo coverings or firmly adhering adhesive residue.
  • Sopro MGR 637 multi-purpose primer: Moisture-sensitive substrates, e.g. magnesium oxychloride (magnesite) screeds and calcium sulfate (anhydrite and self-levelling anhydrite) screeds.

Standard product features

Technical characteristics:

  • Compressive strength: C20.
  • Flexural strength: F5.
  • Water requirement: 5.25–5.75 L per 25 kg.
  • Coverage: 1.6 kg/m² per mm coat thickness.
  • Ready to receive covering: After 24 hours (approximately).
  • Application temperature: 5–25°C (substrate, air, material).
  • Reaction to fire: Class A1 fl.

NBS Specification

NBS Create logo
This product is associated with the following NBS Create clause:
45-55-10/385 Self smoothing levelling screed mix

Product specification

An important note about specifying



SMET Building Products Ltd


+44 (0)28 30266833

Product reference

Sopro SLC 578

Manufacturer details

93A Belfast Road,
Co Down, BT34 1QH
Tel +44 (0)28 30266833
Fax +44 (0)28 30267619
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