polished concrete floor overlay


September 30, 2019 | no responses | 996

Findings from over 250 Concrete Flooring Projects

ARE YOU RENOVATING? Thinking Polished Concrete Floors?

There is one most important thing to know first, to help you make a more intelligent decision.


Move over floorboards and step aside tiles, concrete flooring is making its way to the top of the priority list for many CHIC home renovations. Prized for its long list of benefits including; eco-friendly thermal properties, affordability, easy maintenance, durability and its contemporary and natural appearance to name a few, concrete flooring can be the smartest investment in your renovation project. Adding a shag pile rug and a few other elements to the space, polished concrete floors proves to be a winner in modern minimalist home designs and renovations.

Burnished Concrete Floor

  • Burnished concrete is a polished concrete floor finish where there is no aggregate exposed.
  • Highly sort after in today’s concrete flooring environment.
  • Can only be achieved with a new concrete pour, or topping slab.

Polishing existing or underlying concrete floors requires investigation and planning. Done diligently, the outcome will amaze visitors with its great looks and impress the home owners with its functionality and easy maintenance. And all going well, you’ll be able to move back into your gorgeous dream home, in time and on schedule.

If proper investigation and planning are not carried out, and one proceeds to polish the existing concrete foundation slab, the concrete floor can reveal some unpleasant surprises, often heartbreaking, and the results can be very unpredictable and unacceptable. It is best to have a good indication of the expected concrete floor finish to avoid disappointment, that can also, often lead to lengthy delays whilst researching alternative floor coverings, unexpected changes in floor heights causing unforeseen and costly variations in the building contract, and just to top it off, further delays in the renovation project schedule and families moving back in, which can seriously blowout costs and keep you awake at night.

How do we know?

With the experience gained from well over 250 concrete flooring and resurfacing projects, with consultations and advice given on 100s of unfortunate situations for Architects, Interior Designers, Shop Fitters, Builders and Home Owners. In most cases, to solve a very common problem. This problem could so very easily be avoided with a thorough investigation and assessment of the concrete floor, enabling you to accurately plan the finishes schedule from the very beginning. But unfortunately, a lot of people make a blind decision on one of the most important aspects of their building renovation, being an aesthetically pleasing and functioning concrete floor surface.

So what is the most important thing with polished concrete floors?

If you are considering polished concrete floors or you are already committed to pulling up your existing floor coverings and having a savvy concrete floor finish in your home renovation plans, then the most important thing is actually a most important question you need to ask BEFORE you pledge to the idea. As simple as it sounds, this is it.

Is the underlying concrete suitable to be polished?

I know, simple right?

Let’s talk about the concrete itself.

Concrete that is engineered to be polished is usually specified at 40MPA compressive strength or sometimes 32MPA, and concrete under 32MPA is generally considered too soft and not recommended for honing or polishing. Typical ground-level homes that don’t have polished concrete specified are built on a 25MPA concrete foundation slab. A good concrete polisher can still achieve reasonable results with a 25MPA concrete slab by densifying the surface in the polishing process.

Some older buildings, particularly in the inner suburbs will often have even softer concrete, due to varying factors such as age, poor placement, curing and finishing, that is sometimes spalling or curling or has dropped its level at one or more sides of the building or all of the above. This type will usually require repair, patching and levelling. Also, older buildings that have been renovated previously (several times) will have other factors that will determine the concrete floor as non-polishable, such as extensions.

Non-Polishable Concrete

Grinding back and polishing this type of concrete floor can reveal many undesirable imperfections. And YES, I know what you are probably thinking. “I love the imperfections”. But, these imperfections can be unsightly and a lot worse than you think.

Sometimes the concrete may even appear to be polishable, only to reveal some unexpected apparitions. For example; The concreters rubbish and cigarette butts tossed in, fallen leaves and twigs, footprints etc all trowelled over and concealed. The list of imperfections goes on and on because when the concrete foundation slab was poured, it was never meant to see the light of day, and the concrete polishing process involves grinding the top layer of the surface and so the concealed becomes revealed. Nobody can control where these will appear. Right in the middle of the entrance hallway? Damn.

Also, the tools used to lay the concrete, screed marks, bull float lines, over vibrated areas causing aggregate to fall well below the surface resulting in bold patches (no aggregate exposed), are not those imperfections that we would call desirable. These unsightly variances can appear after the grinding has commenced. 

Tips: If possible, have a tradesperson pull up some or all of the floor covering and inspect the state of the underlying concrete. Easy if its carpet, not so easy with tiles. Laminate is usually glued down but relatively easy to pull up with the right tools.

Things to look for are;

Stains, cracks, soft or chalky surface, levelling or patching compounds applied, levelness, concrete slab extensions or other adjoining flooring substrates, holes or cut off pipes, dynabolts, etc

The type of floor covering that you are pulling up can also have an impact in determining if your underlying concrete is suitable to be polished.

Tiles: pulling up tiles can often leave chipping on the concrete surface from jackhammering the tiles off but thoughtful removal can avoid this and a good concrete polisher can patch these and sometimes blend them in, to a reasonable state. But even worse is the tile ghosting or tile shadow that often can’t be removed no matter how good the concrete polisher is.

Tile ghosting

Timber: Pulling up timber floors can reveal a number of things that will determine if your concrete is suitable to be polished. Mainly levelling compound on the concrete surface as timber likes to be laid on a nice flat concrete substrate. You may also find a neat pattern of holes as timber is often bolted down. These holes can be patched up but will not be invisible.

Timber Floor Removal

Carpet: Pulling up carpet will leave chip holes around the perimeter of the rooms caused be yanking out the carpet gripper as they are nailed down. Also with carpet, depending on the age of the place, there may be staining that has penetrated into the concrete caused by years of spillages, that can not be removed when polishing the concrete floor.

Patching Carpet Gripper Nail Holes


An alternative to polishing concrete floors is to apply a concrete resurfacing material made from cement, so it retains that genuine concrete look. With varying colours and finishes to choose from that can be retrofitted on repaired concrete floors or even directly over tiles, and that can be applied to new structures as well.

Do what Mel Zammit and 100’s of others have done.


Ecoflor® MicroConcrete Flooring is trowel applied with just the right amount of imperfections.

  • Only 2mm thick
  • Genuine burnished concrete look
  • Patch, repair, and level before applying
  • Matt or Satin finish
  • Huge range of colours