Only really developed in the last decade, Premix GRC offers many of the benefits of GRC but in a lower cost form. In this method of production shorter fibres (typically 13mm) are introduced to the matrix at the mixing stage. In order to retain the viscosity required to pour the material into the mould the fibre percentage is reduced to 2-3%, water/cement ratio is increased and other additives incorporated to assist flow.
The material has a lower tensile and bending strength than Spray GRC and is consequently generally used where the geometry of the component gives added stiffness or panels are relatively small with thicker sections.
Premix GRC can be used to manufacture large cladding panels however the stress analysis modelling generally results in panels which are significantly thicker than their Spray Process counterparts. Such designs are generally discarded due to high cost and weight.