Concrete grinding

Concrete grinding uses a heavy machine with diamond pads or segments to wear the surface down. Sika, a flooring manufacturer, says grinders with diamond pads create a surface profile, remove high spots, and remove coatings, mastic, urethane, epoxy, paint and other contaminants.

Sika also says concrete must be mechanically prepared to remove cement laitance, existing coatings and curing compounds, so the new material can bond. Grinding is one of the methods it names, along with shotblasting.

Two cautions apply for older Missouri buildings. First, old adhesive can contain asbestos, as covered in mastic. Test before you grind it. Second, grinding makes dust, so the crew should use a dust collection system.

Grinding is the base of two finishes. In polished concrete it is the coarse first stage. Before an epoxy coating, it creates the surface profile the coating bonds to.

Ask what profile your coating needs and how the crew will check it before they start.