Exterior, New, Renovations, Residential, Commercial, Industrial.
Polished concrete floors provide an affordable alternative to expensive
floor treatments – a look designers and decorators are implementing
creatively in projects ranging from classical to contemporary, rustic
or sophisticated. Concrete floors can be polished to expose aggregate
to replicate the look of polished stone. Polished concrete opens
up an array of design opportunities, providing a creative alternative
to new, tired or concealed concrete. In recent years, concrete has
increasingly become the material of choice for many floors. Polished
concrete is cost effective, durable, low maintenance, hygienic,
dust and allergy free, seamless, energy efficient, proven over centuries,
and has superior aesthetic appearance.
About Polished Concrete
Polished concrete floors provide an affordable alternative
to expensive floor treatments, with a wide range of colours and
finished that are comparable in terms of appearance, to those of
tiles, vinyl and cork. They are energy efficient and offer a low
maintenance and dust free floor. The concept of a polished finish
dates back some 20 to 30 years and was originally used to describe
the process whereby a typical grey or coloured concrete floor was
coated with a wax product and then highly polished. The wax used
was generally powdered beeswax. The surface was then polished by
rubbing vigorously with a soft cloth, hence the term “polished
concrete floors”. These days while the name remains, the final
surface finish can be achieved in a variety of ways. Modern finishes
such as liquid polishes, latex coatings, chemical sealers, grinding
(to expose the aggregates), using colours and special aggregates
to achieve ‘rock or marble’ type finishes are all economical
ways of achieving a variety of effects. Polished concrete finishes
have been generally associated with slab-on-ground type construction.
However with the variety of economical concrete solutions currently
available for suspended slabs, there is no limit to the application
of polished concrete floors.
Achieving the Surface Finish
Because of the ‘polished’ look of the surface
a good quality steel trowelled finish is usually required to the
concrete surface. However some people consider a few trowelling
marks create texture and add interest to the finish. Power trowelling
by using what is known as a ‘helicopter’ is the easiest
way of producing a very flat, even surface. This is best done prior
to the walls being built, and necessitates the protection of the
slab surface during subsequent construction.
Polished Exposed Aggregate
To achieve this finish the surface of the slab is ground to remove
the cement paste, in order to expose the aggregate or stones within
the concrete or topping mix. The surface is then polished using
progressively finer grinding pads. Usually because the cost of grinding
or polishing is an additional expense, special aggregates are often
selected to achieve the best appearance from this type of finish.
Aggregate colours, types (round or crushed), sizes, minerals etc
can all be selected and blended to achieve the desired effect. Two
things need to be remembered: the hard durable aggregates used in
decorative concrete mixes will increase the cost of grinding pads
as they will wear faster. On the other hand, fewer grades of pads
(coarse to fine) are required to produce a polished finish on a
concrete slab. Overall, the cost should still be less than that
of a tiled finish to the slab, and the possible effects can be stunning.
Secondly, it is easier to grind the slab prior to walls being built
because there are no edges or corners to worry about. In this case,
protection of the surface is required.
Sealing the Surface
The final process involved in a polished floor is the application
of a surface sealer. A range of options exist from wax-based products
to various other chemical sealers which give a durable, long-wearing
protective coating to the surface. The skid resistance of polished
concrete floors also needs to be considered as the sealed surface
can become slippery when wet. The use of measures to provide skid
resistance therefore overcomes any problem using this finish outdoors.
Polished concrete floors are easy to maintain with only regular
cleaning required. The sealer prevents staining and should keep
the finish looking good for years.
The current trend towards a low maintenance and dust free
(and hence reduced dust mite) environment, produces a healthier
living environment generally. Polished concrete floors are an ideal
low cost solution, well suited to houses designed using passive
solar design techniques. To produce energy efficient housing, more
and more people are utilising the inherent benefits of concrete
slabs. As concrete slabs are a lifetime investment, long term durability
is also achieved. Whenever the finish starts looking a little dull,
recoating can easily restore the floor to its original appearance.
(FROM ‘BRIEFING 05 AUGUST
2001’ THE CEMENT AND CONCRETE ASSOCIATION OF AUSTRALIA)