Repair Systems
Self-levelling underlayments
Cement-based self-levelling floor underlayment — technical reference for magnesite flooring deterioration in Australian remedial building practice. Covers system selection, product comparisons, and brand equivalents.
What is self-levelling underlayments?
Self-levelling underlayments (SLUs) are poured cement-based compounds that spread under their own flow to produce a smooth, flat surface over prepared and primed magnesite prior to installation of new floor coverings. They are essential in magnesite remediation where the existing screed surface has become uneven, damaged, or corroded, and where hard floor coverings such as timber, vinyl, tile, or carpet require a flat, stable substrate within tight planarity tolerances (typically ±3 mm under a 3 m straight edge). SLUs must be applied over a moisture-suppression primer — never directly to unprepared or damp magnesite. Products are mixed with a measured volume of water and poured onto the primed surface, spreading to a uniform thickness of 3–20 mm without screeding. Coverage is approximately 1.6–1.7 kg/m² per mm of depth. Rapid-setting variants allow floor coverings to be installed within 24 hours.
Product Reference
Scroll right to see all brands. Use each card's TDS link for verified specifications before specifying on any project.
Sika Level-01 Top
cement-based self-levelling underlayment 3–20 mm, 25 kg bag
System Description
Apply over fully cured moisture suppression primer. Pour and spread to required depth — product self-levels within tolerance. Minimum application thickness 3 mm. Do not apply directly to magnesite without moisture primer. Allow full cure before installing floor coverings — typically 24–48 hrs depending on thickness and ambient conditions. Inspect for pinholes and touch up before covering.
Technical Properties
- Produces a flat substrate within tight planarity tolerances required for hard floor coverings
- Self-levels without screeding — faster and more consistent than hand-laid screeds
Limitations
- Must not be applied directly to magnesite — moisture suppression primer is a mandatory prerequisite
- Application requires a continuous pour — cold joints between pours may crack or curl at edges
PROCUREMENT SOURCES
System Description
Apply over fully cured moisture suppression primer. Pour and spread to required depth — product self-levels within tolerance. Minimum application thickness 3 mm. Do not apply directly to magnesite without moisture primer. Allow full cure before installing floor coverings — typically 24–48 hrs depending on thickness and ambient conditions. Inspect for pinholes and touch up before covering.
Technical Properties
- Produces a flat substrate within tight planarity tolerances required for hard floor coverings
- Self-levels without screeding — faster and more consistent than hand-laid screeds
Limitations
- Must not be applied directly to magnesite — moisture suppression primer is a mandatory prerequisite
- Application requires a continuous pour — cold joints between pours may crack or curl at edges
PROCUREMENT SOURCES
Fosroc Nitofloor FC3
cementitious floor levelling and screed compound, 25 kg bag
System Description
Apply over fully cured moisture suppression primer. Pour and spread to required depth — product self-levels within tolerance. Minimum application thickness 3 mm. Do not apply directly to magnesite without moisture primer. Allow full cure before installing floor coverings — typically 24–48 hrs depending on thickness and ambient conditions. Inspect for pinholes and touch up before covering.
Technical Properties
- Produces a flat substrate within tight planarity tolerances required for hard floor coverings
- Self-levels without screeding — faster and more consistent than hand-laid screeds
Limitations
- Must not be applied directly to magnesite — moisture suppression primer is a mandatory prerequisite
- Application requires a continuous pour — cold joints between pours may crack or curl at edges
PROCUREMENT SOURCES
System Description
Apply over fully cured moisture suppression primer. Pour and spread to required depth — product self-levels within tolerance. Minimum application thickness 3 mm. Do not apply directly to magnesite without moisture primer. Allow full cure before installing floor coverings — typically 24–48 hrs depending on thickness and ambient conditions. Inspect for pinholes and touch up before covering.
Technical Properties
- Produces a flat substrate within tight planarity tolerances required for hard floor coverings
- Self-levels without screeding — faster and more consistent than hand-laid screeds
Limitations
- Must not be applied directly to magnesite — moisture suppression primer is a mandatory prerequisite
- Application requires a continuous pour — cold joints between pours may crack or curl at edges
PROCUREMENT SOURCES
Parchem Flowfill FC
pumpable self-levelling floor compound 2–30 mm, 25 kg bag
System Description
Apply over fully cured moisture suppression primer. Pour and spread to required depth — product self-levels within tolerance. Minimum application thickness 3 mm. Do not apply directly to magnesite without moisture primer. Allow full cure before installing floor coverings — typically 24–48 hrs depending on thickness and ambient conditions. Inspect for pinholes and touch up before covering.
Technical Properties
- Produces a flat substrate within tight planarity tolerances required for hard floor coverings
- Self-levels without screeding — faster and more consistent than hand-laid screeds
Limitations
- Must not be applied directly to magnesite — moisture suppression primer is a mandatory prerequisite
- Application requires a continuous pour — cold joints between pours may crack or curl at edges
PROCUREMENT SOURCES
System Description
Use where fast return to service is required. Mixing is time-critical — use a mechanical spiral mixer and pour within 10 minutes of mixing. Close windows and doors to prevent draughts during application. Do not walk on surface for minimum 2–4 hours. Check manufacturer TDS for floor covering installation timelines after rapid-set SLCs.
Technical Properties
- Produces a flat substrate within tight planarity tolerances required for hard floor coverings
- Self-levels without screeding — faster and more consistent than hand-laid screeds
Limitations
- Must not be applied directly to magnesite — moisture suppression primer is a mandatory prerequisite
- Application requires a continuous pour — cold joints between pours may crack or curl at edges
PROCUREMENT SOURCES
Ardex K 301
rapid-setting self-levelling compound, trafficable 2–4 hrs, 25 kg bag
System Description
Use where fast return to service is required. Mixing is time-critical — use a mechanical spiral mixer and pour within 10 minutes of mixing. Close windows and doors to prevent draughts during application. Do not walk on surface for minimum 2–4 hours. Check manufacturer TDS for floor covering installation timelines after rapid-set SLCs.
Technical Properties
- Produces a flat substrate within tight planarity tolerances required for hard floor coverings
- Self-levels without screeding — faster and more consistent than hand-laid screeds
Limitations
- Must not be applied directly to magnesite — moisture suppression primer is a mandatory prerequisite
- Application requires a continuous pour — cold joints between pours may crack or curl at edges
PROCUREMENT SOURCES
System Description
Use where fast return to service is required. Mixing is time-critical — use a mechanical spiral mixer and pour within 10 minutes of mixing. Close windows and doors to prevent draughts during application. Do not walk on surface for minimum 2–4 hours. Check manufacturer TDS for floor covering installation timelines after rapid-set SLCs.
Technical Properties
- Produces a flat substrate within tight planarity tolerances required for hard floor coverings
- Self-levels without screeding — faster and more consistent than hand-laid screeds
Limitations
- Must not be applied directly to magnesite — moisture suppression primer is a mandatory prerequisite
- Application requires a continuous pour — cold joints between pours may crack or curl at edges
PROCUREMENT SOURCES
Mapei Ultraplan Maxi Plus
rapid self-levelling underlayment 3–30 mm, 25 kg bag
System Description
Use where fast return to service is required. Mixing is time-critical — use a mechanical spiral mixer and pour within 10 minutes of mixing. Close windows and doors to prevent draughts during application. Do not walk on surface for minimum 2–4 hours. Check manufacturer TDS for floor covering installation timelines after rapid-set SLCs.
Technical Properties
- Produces a flat substrate within tight planarity tolerances required for hard floor coverings
- Self-levels without screeding — faster and more consistent than hand-laid screeds
Limitations
- Must not be applied directly to magnesite — moisture suppression primer is a mandatory prerequisite
- Application requires a continuous pour — cold joints between pours may crack or curl at edges
PROCUREMENT SOURCES
Parchem Flowfill RS
rapid-set self-levelling compound, trafficable 3–4 hrs, 25 kg bag
System Description
Use where fast return to service is required. Mixing is time-critical — use a mechanical spiral mixer and pour within 10 minutes of mixing. Close windows and doors to prevent draughts during application. Do not walk on surface for minimum 2–4 hours. Check manufacturer TDS for floor covering installation timelines after rapid-set SLCs.
Technical Properties
- Produces a flat substrate within tight planarity tolerances required for hard floor coverings
- Self-levels without screeding — faster and more consistent than hand-laid screeds
Limitations
- Must not be applied directly to magnesite — moisture suppression primer is a mandatory prerequisite
- Application requires a continuous pour — cold joints between pours may crack or curl at edges
PROCUREMENT SOURCES
Brand Equivalents
Side-by-side view of equivalent products across all major brands.
| Material | Ardex | Sika | Fosroc | Tremco / Other | Parchem / Mapei |
|---|---|---|---|---|---|
| Cementitious self-levelling compound | Ardex K 15 | Sika Level-01 Top | Fosroc Nitofloor FC3 | Parchem Flowfill FC | Mapei Ultraplan Eco |
| Rapid-setting self-levelling compound | Ardex K 301 | Sika Level-125 | Fosroc Nitofloor RS | Parchem Flowfill RS | Mapei Ultraplan Maxi Plus |
Disclaimer
Information is general only. Product selection must be confirmed against project requirements, substrate condition, exposure class, manufacturer technical data sheets, NCC requirements, Australian Standards (including AS 3600), and consultant or structural engineer specifications. Do not rely on this reference as a substitute for professional engineering advice.
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