Kiilto HardPlan
Smoothing compound

A fibre-reinforced, fast drying, special cement based smoothing compound for interior and exterior areas. Gives a very hard and smooth surface. Suitable also for levelling floors to be painted and coated. Low alkali.

Special features

  • very hard, self-levelling, fibre-reinforced, fast, paintable
  • wooden and woodpanel floors, general levellings
  • coverage 1.6 kg/m²/mm
  • walkable: 1 h
  • coatable: 5 mm/10 h, 20 mm/ 2 d
  • interior and exterior areas




For smoothing floors at thicknesses 2–20 mm in interior and exterior areas prior to installation of flooring or application of coating. Suitable to be applied over electric under floor heating systems in interior areas, over an area of max. 15 m².

When finishing the floor with vinyl flooring, LVT tile or similar, the recommended layer thickness is 2–20 mm.

If the floor will be painted, coated with polyurethane/epoxy coating, or if the floor is located outdoors, the recommended layer thickness is 4–20 mm.

Suitable for homes and offices, roofed terraces and balconies, residential garages, storages, air-conditioning rooms and engineering and utility services room. In interior areas with light traffic, the finished HardPlan layer can be left uncoated and used as such. If applying paint or coating on the finished HardPlan layer, check the substrate requirements from the paint/coating supplier.

The substrate must be clean, solid and firm. Remove cement laitance, paint splashes, adhesive residue and other impurities, and brush or vacuum the floor properly.

Concrete subfloors are pre-treated with diluted Kiilto Start Primer (1:4) or PrimerOne (20 % Kiilto PrimerOne /80 % water) prior to floor screed. Renovated or board floors are treated with undiluted Kiilto Start or PrimerOne primer before floor screed. Non-absorbent substrates, such as ceramic tiles or painted surfaces can be treated with Kiilto Fix Primer. In exterior areas, prime the surface with Kiilto Fix Primer. In ground concrete floors, capillary moisture must be prevented from entering the structure.

A low alkaline screed layer protects the adhesive and vinyl coating from the damage caused by alkaline moisture in the concrete. The studies have shown that a 5 mm thick screed layer provides the protective effect.

The concrete substrate must comply with national standards.

Package Size EAN Code
20 kg 6411512183206
Application temperature

Optimal +18–23 °C, minimum +10 °C

Bond strength

> 2,0 MPa, EN 13813

Classifications and certificates

CT-C40-F10 (EN13813), M1


2–5 mm / 10 h
20 mm / 2 d
( 23 ºC, 50 % RH )

Compression strength

C40 ( > 40 MPa), EN 13813


1.6 kg/m² (a layer of 1 mm)
One bag provides approx. 12 litres screed.

Fire class


Flexural strength

F10 ( > 10 MPa), EN13813

Frost resistance


Layer thickness

2-20 mm

Max. grain size

approx. 0.6 mm

Mixing ratio

4.0-4.5 l water / 20 kg bag

Package sizes

20 kg bag


< 0,5 ‰ ( 23 ºC, 50 % RH )


In an unopened package, in dry conditions, max. 12 months.

Substrate humidity

Concrete < 90 % RH


polymer-special cement-quarztbased powder


Flow rate 130–140 mm


approx. 1 h ( 23 ºC, 50 % RH )

Working time

n. 20 min ( 23 ºC, 50 % RH )


< 11 (low alkali)

Instructions for use

Fill the mixing container with the required amount of clean water. Strew HardPlan powder slowly while stirring in cool (+10–25 °C), clean water until a smooth, flexible mass is formed. Let the mix mature for approx. 2 min and then remix once before use.

Apply the screed evenly by using a steel or notched trowel. Screed can be applied also by an appropriate floor screed pump. The first layer must be dry before applying a new one.

The drying of the screed must not be accelerated e.g. by heat or ventilation, since too fast drying may cause hair cracks. If the temperature in the levelled room is higher than normally, the relative humidity very low, or if the levelled floor surface is exposed to direct sunlight, we recommend covering the floor with a tarpaulin as soon as it is dry enough to allow walking. The floor should be covered with a flooring relatively soon after it has hardened and dried. This will prevent the surface from over drying, cracking and loosening. If the floor will be left uncoated/uncovered, treat the surface with Kiilto 704 BSP Jälkihoitoaine curing and dust binding agent.

In areas to be waterproofed, such as bathroom floors, the screed is applied beneath the waterproofing.

Not suitable for areas permanently under water (e.g. swimming pools).

Note! Avoid excessive use of water, since it will weaken the substrate's strength and may cause separation and cracking.

Additional information

The information given in this product data sheet is based on our tests and our practical knowledge. The technical data is defined in standard conditions. Variations in local working conditions and methods will affect the product performance and result. The result is also strongly affected by working methods. We guarantee the high quality of our products according to our Quality Management System. No liability can be accepted from incorrect use of the product or prevailing conditions, over which we have no control. Thus, we cannot be held responsible for the final result. To use the product properly, please read the product brochure, work instructions and the safety data sheet available at

Environment and safety

Avoid unnecessary skin contact and exposure with the fresh product, use safety gloves. Refer to the material safety data sheet. For information on product and package disposal, visit