Dry Shake Toppings

Summary

Dry Shake Toppings - A dry shake topping is a thin cementitious layer which can be added to the top of a slab following the initial laying of the concrete.

Technical Information

A dry shake topping is applied by spreading a dry blend of cement, fine aggregate, admixtures and sometimes pigments over the top of a concrete slab whilst it is curing. It relies on the bleed water from the slab in order to hydrate and if there is not enough bleed water present, there is a high risk of delamination. It is typically blended in a factory and come in bags ready to be applied, typically with a mechanical topping spreader.

Some reasons for using dry shake toppings are:

To suppress steel fibres at the surface of the slab.
To colour the surface of the slab.
To cover protruding fibre reinforcement.
To improve abrasion resistance.
They are a cheap overlay option.

If a pigment is used, the final colour of a dry shake topping will not turn out as bright or uniform in colour as a resin or paint coating. The appearance of small laboratory samples will not be reflective of the whole finished floor. Usually, if a light coloured pigment is used, it will give the floor improved light reflectivity.

A dry shake topping can be wholly or partially removed by grinding.