Acid Etching

Summary

Acid Etching - A type of surface treatment in which acid is used to remove laitance and profile the surface of a concrete slab.

Technical Information

Acid etching is carried out by applying concentrated or diluted acid (usually hydrochloric) onto the surface of a concrete slab. The acid reacts with the concrete, removing a thin layer at the top and leaving the surface textured and unsealed. The depth of concrete removed by the acid depends on the acid’s concentration and the exposure time. The process can be repeated if a greater depth of exposure is required. It is important to ensure that a surface is clean before it is acid etched; grease and oil stains should be treated using a degreaser prior to applying the acid.

Acid etching can be used to prepare a surface for the application of a resin or cementitious floor system or to simply improve the concrete surface’s slip resistance.

It is important to ensure that the acid is neutralised and disposed of correctly once the process is complete, which can be quite time consuming. When carrying out acid etching it is essential that current COSHH Regulations are followed, together with the manufacturers guidelines.