Polished concrete: cost-effective, high-end finish.

If you are laying a new concrete floor or have an existing concrete subfloor, you don’t need to cover it. The cement, sand and stone can be ground and polished to a terrazzo type finish for a cost-effective alternative to marble, terrazzo and granite and can result in a high-end, durable floor. The composition of the concrete will naturally dictate the finished result.

Most modern buildings are built on a concrete slab; polishing it eliminates the energy and material consumed by applying a floor covering. It is something to consider when building or modernising towards a more “green” solution.

A laitance polish is where only the very thin top layer of the concrete is polished to a finish. It is carried out with a multi-head grinding machine fitted with resin diamonds or a very fine and gentle pass with metal diamonds first, so as to not expose any aggregate. The importance of a good initial concrete install is critical, as this method is only polishing the top layer and will not level out a badly laid, uneven surface. A minimal amount of material is removed which gives a deep cloudy look with plenty of character.

An exposed aggregate polish is produced by removing the top surface laitance and grinding down to the centre of the first layer of aggregate, then polishing to a terrazzo type finish to the degree of shine require.

When new concrete is laid, colouring agents and coloured aggregate can be incorporated into the mix to produce a decorative effect. It is important that the concrete is laid in a uniform manner to produce a consistent finish.

When the concrete floor is old, uneven or covered, it isn’t ready to simply start the polishing process, another preparation method may be needed first such as stripping or planing to remove old materials or level the floor out. Before considering concrete polishing, it also needs to be established if the surface is cracked or has evident defects and what type of aggregate it is; its size, colour mix and percentage.

After completing the grinding process and in the early resin stage of the polishing, a chemical hardener or densifier can be applied. The timing of this depends on the composition of the concrete. The densifier bonds the surface, provides extra protection from contaminant penetration and produces a better polish. It reacts with the calcium hydroxide in the concrete to form a hard, crystalline structure. It is essential that the last grind prior to applying the densifier is scratch free, as the resulting hardened surface makes removing scratches much more time consuming.

When the polishing process is complete and to uphold the floor’s sustainability credentials, the only maintenance required is cleaning using a diamond infused pad and water such as Storm Diamond Pads, suitable for an STG450, Burnisher or Rotary Scrubber Dryer.

The Preparation Group, based in Lincoln, is a specialist in polishing hard surfaces, carrying out projects nationwide. The company operates PPC, the largest surface preparation, removal and finishing contracting service in the UK, removing, polishing and cleaning floors through to refurbishing car park surfaces and steel platforms.

The company also develops, manufactures and sells a large range of surface preparation, equipment and accessories including accompanying dust extraction. It offers equipment to hire, training, repairs, servicing and project advice.

For further information, a no obligation site survey or quotation call: 01522 561460.