Concrete Grinding and Floor Preparation
Concrete grinding uses diamond tooling to remove a thin layer from the surface of a slab. It takes off weak laitance, old coatings, adhesive residue and minor high spots, leaving a sound, open surface. Sometimes grinding is the preparation for a coating; sometimes it is the first stage of polished concrete. We agree which outcome you need before choosing the tooling and the depth of the grind.
Where this works
- Preparing slabs for resin or epoxy coatings
- Removing old paint, adhesive and failed coatings
- Reducing minor high spots and trowel marks
- The first stages of a polished or honed concrete floor
How we install it
- 1Survey the slab and its history
Grinding starts with knowing what is on and in the floor. We check for existing coatings, adhesives, oil contamination, cracks and joints, and whether the slab is sound. Moisture is relevant if a coating will follow. Knowing what will be applied next decides how far to grind: a resin primer needs a different profile from a floor that will be polished.
- 2Remove coatings and weak surface
Coarser diamonds take off paint, adhesive and laitance first. Heavily built-up coatings can take several passes. Edges and corners that a large machine cannot reach are dealt with by hand tools so the prepared surface is consistent to the walls. Dust extraction runs throughout, which keeps the work area cleaner and makes it easier to inspect the exposed concrete.
- 3Refine to the required profile
For a coating, grinding stops at a profile that gives the primer a good key. For polished concrete, the floor is taken through progressively finer grits, often with a densifier, until it reaches the agreed sheen. At this point defects become visible, so cracks, holes and failed joints can be repaired before the next system is applied.
- 4Clean down and hand over
The ground floor is vacuumed and checked before coating or polishing. If another trade is applying the next layer, agree how long the prepared floor will wait and how it will be protected, because dust and spills can contaminate it. We explain what was removed and any defects found so the next stage is planned on the actual condition of the slab.
Floor grinding before a resin coating
Most coating failures trace back to preparation. Floor grinding removes the weak top layer and contamination that stop primers bonding. It is often preferred to acid etching because it leaves a consistent, dry surface that can be inspected straight away. Our resin floor preparation and coating pages explain what happens after grinding.
Grinding as the start of polished concrete
Polished concrete uses the same machines but goes much further, refining the surface through fine grits and densifying it to a honed or glossy finish. If you want the concrete itself to be the finished floor, our concrete polishing page covers the full process, aggregate exposure and sheen levels.
What affects the cost of concrete grinding?
The area matters, but so do the coatings to be removed, the hardness of the concrete, access for the machines, edge work and the finish required. Removing a thick old coating takes longer than opening up a clean slab. A clear quote states the depth of grind, edge treatment and any repairs separately.
Common pitfalls we prevent
Frequently asked
What is concrete grinding used for?+
It removes weak surface concrete, old coatings, adhesives and minor high spots, either to prepare for a coating or as the first stage of polished concrete.
Is concrete grinding dusty?+
Grinding produces fine dust, so the machines are used with extraction. Work areas are still protected and the floor is vacuumed before the next stage.
How long does floor grinding take?+
It depends on the area, any coatings being removed, the hardness of the concrete and the edge work. A thick coating takes more passes than a clean slab.
Can grinding level an uneven floor?+
It can reduce minor high spots and trowel marks. Larger level differences usually need a screed or levelling system rather than removing large amounts of concrete.
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