Bemix F4


Bemix F4 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.

Product data

Article Number:




25 kg á 40 bags/palette

1000 kg

Product category

Expanding mortar

Expanding mortar


Jointing, Pumpable Jointing, 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 in litres



Yes Yes



Clean the substrate carefully and if possible pre-water 24 hours before casting.


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. In sub-zero temperatures use Bemix F4 FF.

Application advice:

The surfaces of the joins should be clean and free of dust, damaged concrete, grease or other contaminants that could impair adhesion. Pre-water for at least 24 hours. Remove surface water immediately before casting. Rough surfaces give better adhesion. The concrete is applied manually and carefully packed. The concrete 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 finishing trowel. Free and undamaged surfaces should be treated immediately after casting with a thin, light misting of water that cannot mechanically damage the material. As soon as it is hard, water for a long period and cover with plastic. Keep the concrete damp for at least a week after application and try to keep an even temperature of 15˚C while it is curing.