Never underestimate the beauty that lies within concrete. Grinding back the top layer of an interior or exterior concrete floor to reveal the aggregate below can provide you with a spectacular looking floor that is both energy efficient and low-maintenance.
Polished concrete flooring is rapidly becoming a popular choice in many domestic and commercial settings because it delivers great value and an elegant contemporary look. Its smooth and slick finish gives the appearance of natural polished stone, yet it is far more economical, durable and easy to maintain.
A polished concrete floor is achieved by grinding the surface of the slab with metal bond stones to expose the aggregate within the concrete or cementitious topping blend. Whilst the grinding process is occurring the concrete is treated with several specialty liquid compounds that react with the concrete to chemically form calcium silicate hydrate to provide a dense and hard surface which can be gradually mechanically polished with resin bond stones to the level of gloss desired. The final step in the process is to treat the surface with a penetrative sealer to guard against spills and other grime.
For new slabs, you can select the aggregate type and size in addition to the pigment colour of the concrete to create a truly bespoke appearance. Many materials can be added to the concrete mix including coloured and mirror glass and pebbles that glow in the dark.
Generally, there are three levels of aggregate exposure.
Cream/Nil– this is a very minimal exposure level of the fine aggregates and sand only. It can be difficult to achieve as the surface needs to be extremely level and without any undulations. This finish is best suited to new concrete where the slab is laid by highly experienced contractors who can provide the correct finish.
Salt & Pepper– a lighter exposure with a grind depth of approximately 1-3mm to expose the fine aggregates and sand with no larger aggregate pieces visible, depending on how the concrete was poured. This look is quite popular and used in various projects where the appearance is more industrial such as an alfresco area or supermarket.
Full Stone– this is a much heavier grind of approximately 4-6mm to provide the maximum amount of aggregate exposure. The appearance of this is comparable to Terrazzo. It is extremely popular and often used to provide a wow factor in residences, hotels, showrooms and foyers.
In addition to polishing concrete there is another less labour-intensive process called grind and seal. This is a process that mimics polished concrete but without the same amount of work to achieve a similar appearance. It is often mistakenly referred to as polished concrete however, major variances exist between the two as this is a coating process as opposed to a polishing process.
Grind & Seal– This type of floor is achieved by grinding a few times to expose a certain level of aggregate and sometimes grouting imperfections then applying a topical sealer, usually a Polyurethane. This finish is often used in commercial buildings, factories, retail outlets, showrooms and residences. The cost for this type of finish is usually far less than that of polished concrete making it a great option to consider.
Polished Concrete Finishes
Benefits of Polished Concrete
Cost savings and longer life-cycle
Elegant and refined appearance
Scratch resistant with low maintenance costs
Design flexibility and aesthetically diverse options
Full depth colour available
Dust free, seamless and durable