Home > Companies > ARDEX UK Ltd > ARDEX K 15 Levelling and Smoothing Compound

K 15 is a rapid drying self-levelling sub-floor smoothing compound.


  • Improved yield and superior flow and levelling characteristics.
  • Rapid hardening - walk on after 2 hours.
  • Receives floorcoverings the next day, regardless of thickness at 20°C.
  • Apply from feather edge up to 35 mm thick.
  • Can be applied by trowel or pump.
  • Strong - high compressive strength.
  • Suitable for floors with underfloor heating.
  • Ideal for use with ARDEX flooring adhesives.


May generally be applied to any thickness, but non-absorbent sub-floors, e.g. flooring grade asphalt, must be levelled with at least 1.5 mm of ARDEX K15. No more than 6 mm of ARDEX K 15 should be used on top of asphalt.

  • Limitations: ARDEX K 15 is limited to 10 mm thick on ARDEX P 82 primer. This is reduced to 6 mm on ARDEX P 82 when onto ARDEX DPM/ ARDEX DPM 1C/ ARDEX DPM 1CR.

Related literature

The following content references this product:



All surfaces must be primed.

– ARDEX P51:

  • Aqueous synthetic based dispersion primer and bonding agent used to prepare internal surfaces to receive cement-based levelling compounds, adhesives or screeds. Use ARDEX P51 on very absorbent surfaces.

– ARDEX P82:

  • Two-part water based synthetic dispersion primer and bonding agent used to form a priming/ bonding layer on most substrates, particularly smooth or dense surfaces, e.g. smooth power floated concrete including ARDEX DPM/ ARDEX DPM 1C/ ARDEX DPM 1CR.
  • ARDEX P4 - Solvent free rapid drying primer, applied to concrete, screeds, terrazzo and ceramic tiles and can be used externally.

Aggregate filler:

For thicknesses over 10 mm incorporate up to an equal volume of 3 mm single sized chippings. For thicknesses of 20–35 mm up to an equal volume of 3–8 mm aggregate may be added.

NBS Specification

NBS Create logo
This product is associated with the following NBS Create clause:
45-55-10/320 Smoothing or levelling underlayment compound

Product specification

An important note about specifying





+44 (0)1440 714939

Product reference

ARDEX K 15 Rapid Drying Self-Levelling Sub-Floor Smoothing Compound


[Not required]
[P51 primer]
[P82 primer]
[P4 primer]
[Contractor's choice]

Smoothing compound

 - Aggregate filler:
[3 mm ARDEX COARSE Aggregate]
[3 mm single sized chippings]
[3–8 mm chippings]
[Contractor's choice]
 - Amount (by volume):
[Not more than volume of ARDEX K15 compound]

Manufacturer details

Homefield Road,
Suffolk, CB9 8QP
Tel +44 (0)1440 714939
Fax +44 (0)1440 716667
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