Bemix F4 FF


Bemix F4 FF is a thixotropic, expanding, pumpable jointing compound. It is used for sealing and jointing concrete elements and granite blocks. With its thixotropic consistency, it is the first choice for vertical joints. Easily applied with pumping equipment or by hand. Also suitable for horizontal joints and other types of cast joints. Cures in minus degrees without heating.

Product data

Article Number:




25 kg á 40 bags/ palette

1000 kg

Product category

Expanding mortar

Expanding mortar


Jointing, Application in sub-zero temperatures, Pumpable Jointing, Application in sub-zero temperatures, Pumpable

Processable minutes


Compression strength

40 MPa 40 MPa

Layer thickness

5-50 mm 5-50 mm


2 kg/m2/mm 2 kg/m2/mm

Water quantity per 25 kg

4.0 litres

4.0 litres

1 kg dry mortar = finished concrete

0,5 litres 0,5 litres


Yes Yes



The concrete substrate must be clean and free of dust, damaged concrete, grease or other contaminants that may impair adhesion. Substrate with a roughened and raw surface with closely spaced irregularities provide better adhesion. Clean the substrate carefully and if possible pre-water 24 hours before casting. Remove surface water immediately before casting. Do not water when casting in minus degrees. At freezing temperatures, the surface must be defrosted, and ice and melt water removed.


Is done mechanically for approximately 5 minutes in a slow-action mixer, such as a flat or free-fall mixer. Smaller quantities can be mixed with a mixer attachment. The concrete mix should have a temperature of approximately 20°C. Compensate cold dry material with warm water and vice versa.

Application advice:

The mortar is applied manually and carefully packed or can also be pumped with a purpose-designed concrete pump. Ensure that joints and underpourings are always completely filled so as to avoid cavities.

After treatment:

Semi-hardened material can be adjusted with a trowel. Free and unprotected surfaces are protected immediately after casting so that shrinkage and dehydration cracks do not occur. At air temperatures below 5°C, curing may take place by remaining form or covering without water addition and may last the entire first week. Watering should not be done when casting in minus degrees.