Kiilto Maxirapid
Fast-setting screed

An extra fast curing levelling screed for levelling floors, filling and patching gaps and making floor slopes. Ready to receive a floor covering as soon as 2 h after levelling. Suitable to be used under paint or epoxy. Also for exterior applications. Low alkali. Cementitious.

Special features

  •  very fast, paintable 
  • floor corrections, slopes and patchings 
  •  coverage 1.6 kg/m²/mm
  •  walkable: 45 min
  •  coatable: 2 h
  •  interior and exterior areas





Extra fast curing levelling screed for levelling floors, filling and patching gaps and making floor slopes before over levelling and/or laying the floor covering, at thicknesses of 1–30 mm. For over levellings we recommend using, e.g., Kiilto 97 DF, TopPlan DF or Tasoflex levelling compounds. Suitable for interior and exterior use. In exterior applications, minimum layer thickness is 5 mm.
The substrate must be clean, solid and firm. Remove cement laitance and paint splashes, and brush or vacuum the floor thoroughly. Rough uneven areas and high ridges must be sanded before levelling.
Concrete subfloors are pre-treated with diluted Kiilto Start Primer (10–20 % Kiilto Start Primer / 80–90 % water) prior to application of the floor screed. Surfaces under reconstruction as well as board surfaces must be primed with undiluted Kiilto Start Primer before levelling. In outdoor applications and with non-absorbent substrates prime the substrate with Kiilto Fix Primer or make a bond bridge with, e.g., Kiilto Saneerauslaasti cementitious adhesive with a notched trowel. In ground supported structures, the capillary rise of moisture must be prevented.
The concrete substrate must comply with national standards (in Finland SisäRYL 2013 and BY 45).

Package Size EAN Code
20 kg 6411512019208
Application temperature

Optimal +18–20 °C, minimum +10 °C

Bond strength

> 1.5 MPa, EN 13813

Classifications and certificates

CT-C35-F8 (EN13813), M1


approx. 2 hours

Compression strength

C35 (> 35 MPa), EN 13813


1 mm layer/m² solid matter weighs approx. 1.6 kg (approx. 12 litres of screed/bag).

Fire class


Flexural strength

F8 (> 8 MPa), EN 13813

Layer thickness

1–30 mm

Max. grain size

0.4 mm

Mixing ratio

approx. 4.0 l water / 20 kg bag (fillings and slopes)
approx. 4.5 l water / 20 kg bag (over levellings).

Adding of 20–30 % sand (particle size 1–3 mm) is possible, when doing thick fillings.

Package sizes

20 kg bag


< 0.6 ‰ (+23 ºC, 50 % RH )


Unopened package in a dry place 6 months.

Substrate humidity

concrete < 90 % RH


resin-special cement-quartz powder-based powder


Approx. 45 min

Working time

10-15 min.


< 11 (low alkali)

Instructions for use

Mix 20 kg levelling screed powder with 4.0–4.5 l of cool water and stir continuously until a smooth, plastic mix is formed. Apply immediately to a clean floor by using a steel trowel. The floor is walkable in about 45 minutes, and the floor covering can be laid after approx. 2 hours.
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 becoming loose.
Also suitable for floors to be painted in secondary, lightly trafficked areas, but not suitable, for example, for garage floors, wet room floors, etc.
In areas where waterproofing is used, e.g., bathroom floors, floor levelling should be applied under the waterproofing membrane.
Not suitable for areas permanently under water (e.g., swimming pools).
Note! Using more water than instructed will retard the drying process and weaken the strength of the concrete. It may also 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. 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. The correct use of the product presupposes that the user has made him/herself aware of the contents of the working instructions and procedure guide, if provided.

Environment and safety

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